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Trademarks
Copyright © PLANET Technology Corp. 2015.
Contents are subject to revision without prior notice.
PLANET is a registered trademark of PLANET Technology Corp. All other trademarks belong to their
respective owners.
Disclaimer PLANET Technology does not warrant that the hardware will work properly in all environments and applications, and makes no warranty and representation, either implied or expressed, with respect to the quality, performance, merchantability, or fitness for a particular purpose. PLANET has made every effort to ensure that this User's Manual is accurate; PLANET disclaims liability for any inaccuracies or omissions that may have occurred. Information in this User's Manual is subject to change without notice and does not represent a commitment on the part of PLANET. PLANET assumes no responsibility for any inaccuracies that may be contained in this User's Manual. PLANET makes no commitment to update or keep current the information in this User's Manual, and reserves the right to make improvements to this User's Manual and/or to the products described in this User's Manual, at any time without notice. If you find information in this manual that is incorrect, misleading, or incomplete, we would appreciate your
comments and suggestions.
FCC Warning This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the Instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense.
CE Mark Warning This is a Class A product. In a domestic environment, this product may cause radio interference, in which case the user may be required to take adequate measures.
Energy Saving Note of the Device This power required device does not support Standby mode operation. For energy saving, please remove the power cable to disconnect the device from the power circuit. In view of saving the energy and reducing the unnecessary power consumption, it is strongly suggested to remove the power connection for the device if
this device is not intended to be active.
WEEE Warning
To avoid the potential effects on the environment and human health as a result of the presence of hazardous substances in electrical and electronic equipment, end users of
electrical and electronic equipment should understand the meaning of the crossed-out wheeled bin symbol. Do not dispose of WEEE as unsorted municipal waste and have to collect such WEEE separately.
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Revision
PLANET Layer 3 Multi-Port Full Gigabit Stackable Managed Switch User's Manual FOR MODEL: SGS-6340-24T4S/48T4S/24P4S/20S4C4X REVISION: 1.0 (August, 2015) Part No: EM-SGS-6340-24T_48T_24P4S_20S4C4X (2081-A96240-000)
Contents
CHAPTER 1 INTRODUCTION ........................................................................................ 1-1
1.1 PACKET CONTENTS ............................................................................................................................. 1-1
1.2 PRODUCT DESCRIPTION ....................................................................................................................... 1-1
1.3 PRODUCT FEATURES ........................................................................................................................... 1-4
1.4 PRODUCT SPECIFICATIONS................................................................................................................... 1-6
CHAPTER 2 INSTALLATION............................................................................................18
2.1 HARDWARE DESCRIPTION ..................................................................................................................... 18 2.1.1 Switch Front Panel ................................................................................................................... 18 2.1.2 LED Indications ........................................................................................................................ 19 2.1.3 Switch Rear Panel.................................................................................................................... 23
2.2 INSTALLING THE MANAGED SWITCH....................................................................................................... 25 2.2.1 Desktop Installation.................................................................................................................. 25 2.2.2 Rack Mounting ......................................................................................................................... 26 2.2.3 Installing the SFP/SFP+ Transceiver ....................................................................................... 27
CHAPTER 3 SWITCH MANAGEMENT .......................................................................... 3-1
3.1 MANAGEMENT OPTIONS....................................................................................................................... 3-1 3.1.1 Out-of-Band Management....................................................................................................... 3-1 3.1.2 In-band Management .............................................................................................................. 3-4
3.2 CLI INTERFACE.................................................................................................................................... 3-9 3.2.1 Configuration Modes ............................................................................................................. 3-10 3.2.2 Configuration Syntax............................................................................................................. 3-12 3.2.3 Shortcut Key Support ............................................................................................................ 3-13 3.2.4 Help Function ........................................................................................................................ 3-13 3.2.5 Input Verification.................................................................................................................... 3-14 3.2.6 Fuzzy Match Support ............................................................................................................ 3-14
CHAPTER 4 BASIC SWITCH CONFIGURATION .......................................................... 4-1
4.1 BASIC CONFIGURATION........................................................................................................................ 4-1
4.2 TELNET MANAGEMENT......................................................................................................................... 4-2 4.2.1 Telnet....................................................................................................................................... 4-2 4.2.2 SSH......................................................................................................................................... 4-4
4.3 CONFIGURE SWITCH IP ADDRESSES..................................................................................................... 4-6 4.3.1 Switch IP Addresses Configuration Task List.......................................................................... 4-6
4.4 SNMP CONFIGURATION....................................................................................................................... 4-8 4.4.1 Introduction to SNMP.............................................................................................................. 4-8 4.4.2 Introduction to MIB .................................................................................................................. 4-9 4.4.3 Introduction to RMON ........................................................................................................... 4-10
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4.4.4 SNMP Configuration ............................................................................................................. 4-10 4.4.5 Typical SNMP Configuration Examples ................................................................................ 4-14 4.4.6 SNMP Troubleshooting ......................................................................................................... 4-15
4.5 SWITCH UPGRADE ............................................................................................................................. 4-16 4.5.1 Switch System Files .............................................................................................................. 4-16 4.5.2 BootROM Upgrade................................................................................................................ 4-16 4.5.3 FTP/TFTP Upgrade............................................................................................................... 4-19
CHAPTER 5 FILE SYSTEM OPERATIONS...................................................................5-29
5.1 INTRODUCTION TO FILE STORAGE DEVICES......................................................................................... 5-29
5.2 FILE SYSTEM OPERATION CONFIGURATION TASK LIST ......................................................................... 5-29
5.3 TYPICAL APPLICATIONS...................................................................................................................... 5-31
5.4 TROUBLESHOOTING ........................................................................................................................... 5-31
CHAPTER 6 CLUSTER CONFIGURATION.................................................................... 6-1
6.1 INTRODUCTION TO CLUSTER NETWORK MANAGEMENT............................................................................ 6-1
6.2 CLUSTER NETWORK MANAGEMENT CONFIGURATION SEQUENCE........................................................... 6-1
6.3 EXAMPLES OF CLUSTER ADMINISTRATION ............................................................................................ 6-6
6.4 CLUSTER ADMINISTRATION TROUBLESHOOTING.................................................................................... 6-6
CHAPTER 7 PORT CONFIGURATION........................................................................... 7-8
7.1 INTRODUCTION TO PORT ...................................................................................................................... 7-8
7.2 NETWORK PORT CONFIGURATION TASK LIST ........................................................................................ 7-8
7.3 PORT CONFIGURATION EXAMPLE ....................................................................................................... 7-11
7.4 PORT TROUBLESHOOTING.................................................................................................................. 7-12
CHAPTER 8 PORT ISOLATION FUNCTION CONFIGURATION..................................8-13
8.1 INTRODUCTION TO PORT ISOLATION FUNCTION.................................................................................... 8-13
8.2 TASK SEQUENCE OF PORT ISOLATION................................................................................................. 8-13
8.3 PORT ISOLATION FUNCTION TYPICAL EXAMPLES................................................................................. 8-14
CHAPTER 9 PORT LOOPBACK DETECTION FUNCTION CONFIGURATION ...........9-15
9.1 INTRODUCTION TO PORT LOOPBACK DETECTION FUNCTION ................................................................ 9-15
9.2 PORT LOOPBACK DETECTION FUNCTION CONFIGURATION TASK LIST .................................................. 9-16
9.3 PORT LOOPBACK DETECTION FUNCTION EXAMPLE ............................................................................. 9-17
9.4 PORT LOOPBACK DETECTION TROUBLESHOOTING.............................................................................. 9-18
CHAPTER 10 ULDP FUNCTION CONFIGURATION ..................................................10-19
10.1 INTRODUCTION TO ULDP FUNCTION............................................................................................... 10-19
10.2 ULDP CONFIGURATION TASK SEQUENCE ....................................................................................... 10-20
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10.3 ULDP FUNCTION TYPICAL EXAMPLES ............................................................................................ 10-23
10.4 ULDP TROUBLESHOOTING ............................................................................................................ 10-24
CHAPTER 11 LLDP FUNCTION OPERATION CONFIGURATION .............................11-26
11.1 INTRODUCTION TO LLDP FUNCTION ............................................................................................... 11-26
11.2 LLDP FUNCTION CONFIGURATION TASK SEQUENCE ....................................................................... 11-27
11.3 LLDP FUNCTION TYPICAL EXAMPLE............................................................................................... 11-30
11.4 LLDP FUNCTION TROUBLESHOOTING............................................................................................. 11-31
CHAPTER 12 PORT CHANNEL CONFIGURATION ...................................................12-32
12.1 INTRODUCTION TO PORT CHANNEL................................................................................................. 12-32
12.2 BRIEF INTRODUCTION TO LACP..................................................................................................... 12-33 12.2.1 Static LACP Aggregation................................................................................................... 12-34 12.2.2 Dynamic LACP Aggregation.............................................................................................. 12-34 12.2.3 Port Channel Configuration Task List................................................................................ 12-35
12.3 PORT CHANNEL EXAMPLES............................................................................................................ 12-37
12.4 PORT CHANNEL TROUBLESHOOTING .............................................................................................. 12-39
CHAPTER 13 MTU CONFIGURATION........................................................................13-40
13.1 INTRODUCTION TO MTU ................................................................................................................. 13-40
13.2 MTU CONFIGURATION TASK SEQUENCE ......................................................................................... 13-40
CHAPTER 14 EFM OAM CONFIGURATION...............................................................14-41
14.1 INTRODUCTION TO EFM OAM........................................................................................................ 14-41
14.2 EFM OAM CONFIGURATION .......................................................................................................... 14-44
14.3 EFM OAM EXAMPLE..................................................................................................................... 14-47
14.4 EFM OAM TROUBLESHOOTING ..................................................................................................... 14-48
CHAPTER 15 PORT SECURITY .................................................................................15-49
15.1 INTRODUCTION TO PORT SECURITY............................................................................................ 15-49
15.2 PORT SECURITY CONFIGURATION TASK LIST.............................................................................. 15-49
15.3 EXAMPLE OF PORT SECURITY.................................................................................................... 15-50
15.4 PORT SECURITY TROUBLESHOOTING ......................................................................................... 15-51
CHAPTER 16 DDM CONFIGURATION .......................................................................16-52
16.1 INTRODUCTION TO DDM................................................................................................................. 16-52 16.1.1 Brief Introduction to DDM.................................................................................................. 16-52 16.1.2 DDM Function ................................................................................................................... 16-53
16.2 DDM CONFIGURATION TASK LIST................................................................................................... 16-54
16.3 EXAMPLES OF DDM....................................................................................................................... 16-56
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16.4 DDM TROUBLESHOOTING.............................................................................................................. 16-60
CHAPTER 17 LLDP-MED............................................................................................17-61
17.1 INTRODUCTION TO LLDP-MED ...................................................................................................... 17-61
17.2 LLDP-MED CONFIGURATION TASK SEQUENCE .............................................................................. 17-61
17.3 LLDP-MED EXAMPLE................................................................................................................... 17-64
17.4 LLDP-MED TROUBLESHOOTING ................................................................................................... 17-67
CHAPTER 18 BPDU-TUNNEL CONFIGURATION......................................................18-67
18.1 INTRODUCTION TO BPDU-TUNNEL.................................................................................................... 18-67 18.1.1 bpdu-tunnel function.......................................................................................................... 18-67 18.1.2 Background of bpdu-tunnel............................................................................................... 18-68
18.2 BPDU-TUNNEL CONFIGURATION TASK LIST...................................................................................... 18-68
18.3 EXAMPLES OF BPDU-TUNNEL.......................................................................................................... 18-69
18.4 BPDU-TUNNEL TROUBLESHOOTING ................................................................................................. 18-70
CHAPTER 19 EEE ENERGY-SAVING CONFIGURATION..........................................19-71
19.1 INTRODUCTION TO EEE ENERGY-SAVING ........................................................................................ 19-71
19.2 EEE ENERGY-SAVING CONFIGURATION LIST.................................................................................... 19-71
19.3 EEE ENERGY-SAVING TYPICAL EXAMPLES ..................................................................................... 19-71
CHAPTER 20 VLAN CONFIGURATION......................................................................20-72
20.1 VLAN CONFIGURATION ................................................................................................................. 20-72 20.1.1 Introduction to VLAN......................................................................................................... 20-72 20.1.2 VLAN Configuration Task List ........................................................................................... 20-73 20.1.3 Typical VLAN Application .................................................................................................. 20-77 20.1.4 Typical Application of Hybrid Port ..................................................................................... 20-78
20.2 DOT1Q-TUNNEL CONFIGURATION ................................................................................................... 20-80 20.2.1 Introduction to Dot1q-tunnel.............................................................................................. 20-80 20.2.2 Dot1q-tunnel Configuration ............................................................................................... 20-82 20.2.3 Typical Applications of the Dot1q-tunnel ........................................................................... 20-82 20.2.4 Dot1q-tunnel Troubleshooting........................................................................................... 20-84
20.3 SELECTIVE Q-IN-Q CONFIGURATION............................................................................................... 20-84 20.3.1 Introduction to Selective QinQ .......................................................................................... 20-84 20.3.2 Selective Q-in-Q Configuration ......................................................................................... 20-84 20.3.3 Typical Applications of Selective QinQ.............................................................................. 20-85 20.3.4 Selective Q-in-Q Troubleshooting ..................................................................................... 20-87
20.4 VLAN-TRANSLATION CONFIGURATION............................................................................................ 20-87 20.4.1 Introduction to VLAN Translation ...................................................................................... 20-87 20.4.2 VLAN-translation Configuration ........................................................................................ 20-88 20.4.3 Typical Application of VLAN Translation ........................................................................... 20-89 20.4.4 VLAN-translation Troubleshooting .................................................................................... 20-90
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20.5 MULTI-TO-ONE VLAN TRANSLATION CONFIGURATION .................................................................... 20-90 20.5.1 Introduction to Multi-to-One VLAN Translation ................................................................. 20-90 20.5.2 Multi-to-One VLAN Translation Configuration................................................................... 20-90 20.5.3 Typical application of Multi-to-One VLAN Translation....................................................... 20-91 20.5.4 Multi-to-One VLAN Translation Troubleshooting .............................................................. 20-93
20.6 DYNAMIC VLAN CONFIGURATION................................................................................................... 20-93 20.6.1 Introduction to Dynamic VLAN.......................................................................................... 20-93 20.6.2 Dynamic VLAN Configuration ........................................................................................... 20-94 20.6.3 Typical Application of the Dynamic VLAN......................................................................... 20-96 20.6.4 Dynamic VLAN Troubleshooting ....................................................................................... 20-97
20.7 GVRP CONFIGURATION ................................................................................................................. 20-98 20.7.1 Introduction to GVRP ........................................................................................................ 20-98 20.7.2 GVRP Configuration Task List........................................................................................... 20-99 20.7.3 Example of GVRP............................................................................................................. 20-99 20.7.4 GVRP Troubleshooting ................................................................................................... 20-102
20.8 VOICE VLAN CONFIGURATION ..................................................................................................... 20-102 20.8.1 Introduction to Voice VLAN ............................................................................................. 20-102 20.8.2 Voice VLAN Configuration .............................................................................................. 20-103 20.8.3 Typical Applications of the Voice VLAN .......................................................................... 20-104 20.8.4 Voice VLAN Troubleshooting .......................................................................................... 20-105
CHAPTER 21 MAC TABLE CONFIGURATION.........................................................21-106
21.1 INTRODUCTION TO MAC TABLE .................................................................................................... 21-106 21.1.1 Obtaining MAC Table ...................................................................................................... 21-106 21.1.2 Forward or Filter.............................................................................................................. 21-108
21.2 MAC ADDRESS TABLE CONFIGURATION TASK LIST........................................................................ 21-109
21.3 TYPICAL CONFIGURATION EXAMPLES ........................................................................................... 21-110
21.4 MAC TABLE TROUBLESHOOTING ..................................................................................................21-111
21.5 MAC ADDRESS FUNCTION EXTENSION ..........................................................................................21-111 21.5.1 MAC Address Binding ......................................................................................................21-111
21.6 MAC NOTIFICATION CONFIGURATION ........................................................................................... 21-114 21.6.1 Introduction to MAC Notification ..................................................................................... 21-114 21.6.2 MAC Notification Configuration....................................................................................... 21-114 21.6.3 MAC Notification Example .............................................................................................. 21-116 21.6.4 MAC Notification Troubleshooting................................................................................... 21-116
CHAPTER 22 MSTP CONFIGURATION....................................................................22-117
22.1 INTRODUCTION TO MSTP............................................................................................................. 22-117
22.2 MSTP REGION ............................................................................................................................ 22-117 22.2.1 Operations within an MSTP Region................................................................................ 22-118 22.2.2 Port Roles ....................................................................................................................... 22-119 22.2.3 MSTP Load Balance ....................................................................................................... 22-119
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22.3 MSTP CONFIGURATION TASK LIST............................................................................................... 22-119
22.4 MSTP EXAMPLE.......................................................................................................................... 22-124
22.5 MSTP TROUBLESHOOTING .......................................................................................................... 22-129
CHAPTER 23 QOS CONFIGURATION......................................................................23-130
23.1 INTRODUCTION TO QOS ............................................................................................................... 23-130 23.1.1 QoS Terms ...................................................................................................................... 23-130 23.1.2 QoS Implementation ....................................................................................................... 23-132 23.1.3 Basic QoS Model ............................................................................................................ 23-132
23.2 QOS CONFIGURATION TASK LIST ................................................................................................. 23-136
23.3 QOS EXAMPLE ............................................................................................................................ 23-141
23.4 QOS TROUBLESHOOTING............................................................................................................. 23-144
CHAPTER 24 FLOW-BASED REDIRECTION...............................................................24-1
24.1 INTRODUCTION TO FLOW-BASED REDIRECTION ................................................................................. 24-1
24.2 FLOW-BASED REDIRECTION CONFIGURATION TASK SEQUENCE ......................................................... 24-1
24.3 FLOW-BASED REDIRECTION EXAMPLES ............................................................................................ 24-2
24.4 FLOW-BASED REDIRECTION TROUBLESHOOTING HELP...................................................................... 24-2
CHAPTER 25 FLEXIBLE QINQ CONFIGURATION ......................................................25-3
25.1 INTRODUCTION TO FLEXIBLE QINQ ................................................................................................... 25-3 25.1.1 QinQ Technique .................................................................................................................. 25-3 25.1.2 Basic QinQ .......................................................................................................................... 25-3 25.1.3 Flexible QinQ ...................................................................................................................... 25-3 25.1.4 Flexible QinQ Configuration Task List................................................................................. 25-3
25.2 FLEXIBLE QINQ EXAMPLE................................................................................................................ 25-5
25.3 FLEXIBLE QINQ TROUBLESHOOTING ................................................................................................ 25-7
CHAPTER 26 LAYER 3 MANAGEMENT CONFIGURATION........................................26-7
26.1 LAYER 3 MANAGEMENT INTERFACE .................................................................................................. 26-7 26.1.1 Introduction to Layer 3 Management Interface ................................................................... 26-7 26.1.2 Layer 3 Interface Configuration Task List............................................................................ 26-7
26.2 IP CONFIGURATION.......................................................................................................................... 26-8 26.2.1 Introduction to IPv4, IPv6.................................................................................................... 26-8 26.2.2 IP Configuration ................................................................................................................ 26-10 26.2.3 IPv6 Troubleshooting ........................................................................................................ 26-13
26.3 STATIC ROUTE............................................................................................................................... 26-13 26.3.1 Introduction to Static Route............................................................................................... 26-13 26.3.2 Introduction to Default Route ............................................................................................ 26-14 26.3.3 Static Route Configuration Task List ................................................................................. 26-14 26.3.4 Static Route Configuration Examples ............................................................................... 26-14
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26.4 RIP............................................................................................................................................... 26-16 26.4.1 Introduction to RIP ............................................................................................................ 26-16 26.4.2 RIP Configuration Task List............................................................................................... 26-18 26.4.3 RIP Examples – Typical RIP ............................................................................................. 26-24 26.4.4 RIP Examples – RIP aggregation function........................................................................ 26-26 26.4.5 RIP Troubleshooting.......................................................................................................... 26-27
26.5 OSPF........................................................................................................................................... 26-27 26.5.1 Introduction to OSPF......................................................................................................... 26-27 26.5.2 OSPF Configuration Task List ........................................................................................... 26-31 26.5.3 OSPF Examples................................................................................................................ 26-36 26.5.4 Configuration Example of OSPF....................................................................................... 26-36 26.5.5 Configuration Examples of OSPF VPN............................................................................. 26-44 26.5.6 OSPF Troubleshooting...................................................................................................... 26-46
26.6 ARP ............................................................................................................................................. 26-47 26.6.1 Introduction to ARP ........................................................................................................... 26-47 26.6.2 ARP Configuration Task List.............................................................................................. 26-47 26.6.3 ARP Troubleshooting ........................................................................................................ 26-47
CHAPTER 27 ARP SCANNING PREVENTION FUNCTION CONFIGURATION.........27-48
27.1 INTRODUCTION TO ARP SCANNING PREVENTION FUNCTION ............................................................ 27-48
27.2 ARP SCANNING PREVENTION CONFIGURATION TASK SEQUENCE .................................................... 27-49
27.3 ARP SCANNING PREVENTION TYPICAL EXAMPLES.......................................................................... 27-51
27.4 ARP SCANNING PREVENTION TROUBLESHOOTING HELP................................................................. 27-52
CHAPTER 28 PREVENT ARP SPOOFING CONFIGURATION ..................................28-53
28.1 OVERVIEW..................................................................................................................................... 28-53 28.1.1 ARP (Address Resolution Protocol) .................................................................................. 28-53 28.1.2 ARP Spoofing .................................................................................................................... 28-53 28.1.3 How to prevent void ARP Spoofing ................................................................................... 28-53
28.2 PREVENT ARP SPOOFING CONFIGURATION..................................................................................... 28-54
28.3 PREVENT ARP SPOOFING EXAMPLE............................................................................................... 28-55
CHAPTER 29 ARP GUARD CONFIGURATION ..........................................................29-57
29.1 INTRODUCTION TO ARP GUARD ................................................................................................... 29-57
29.2 ARP GUARD CONFIGURATION TASK LIST ..................................................................................... 29-58
CHAPTER 30 GRATUITOUS ARP CONFIGURATION................................................30-59
30.1 INTRODUCTION TO GRATUITOUS ARP ............................................................................................. 30-59
30.2 GRATUITOUS ARP CONFIGURATION TASK LIST ............................................................................... 30-59
30.3 GRATUITOUS ARP CONFIGURATION EXAMPLE ................................................................................ 30-60
30.4 GRATUITOUS ARP TROUBLESHOOTING .......................................................................................... 30-61
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CHAPTER 31 DHCP CONFIGURATION .....................................................................31-62
31.1 INTRODUCTION TO DHCP............................................................................................................... 31-62
31.2 DHCP SERVER CONFIGURATION.................................................................................................... 31-63
31.3 DHCP RELAY CONFIGURATION ...................................................................................................... 31-66
31.4 DHCP CONFIGURATION EXAMPLES................................................................................................ 31-68
31.5 DHCP TROUBLESHOOTING ............................................................................................................ 31-71
CHAPTER 32 DHCPV6 CONFIGURATION .................................................................32-72
32.1 INTRODUCTION TO DHCPV6........................................................................................................... 32-72
32.2 DHCPV6 SERVER CONFIGURATION................................................................................................ 32-73
32.3 DHCPV6 RELAY DELEGATION CONFIGURATION .............................................................................. 32-75
32.4 DHCPV6 PREFIX DELEGATION SERVER CONFIGURATION ................................................................ 32-76
32.5 DHCPV6 PREFIX DELEGATION CLIENT CONFIGURATION ................................................................. 32-78
32.6 DHCPV6 CONFIGURATION EXAMPLES............................................................................................ 32-78
32.7 DHCPV6 TROUBLESHOOTING........................................................................................................ 32-80
CHAPTER 33 DHCP OPTION 82 CONFIGURATION..................................................33-82
33.1 INTRODUCTION TO DHCP OPTION 82 ............................................................................................. 33-82 33.1.1 DHCP Option 82 Message Structure ................................................................................ 33-82 33.1.2 Option 82 Working Mechanism......................................................................................... 33-83
33.2 DHCP OPTION 82 CONFIGURATION TASK LIST ............................................................................... 33-84
33.3 DHCP OPTION 82 APPLICATION EXAMPLES ................................................................................... 33-88
33.4 DHCP OPTION 82 TROUBLESHOOTING........................................................................................... 33-90
CHAPTER 34 DHCP OPTION 60 AND OPTION 43 ....................................................34-91
34.1 INTRODUCTION TO DHCP OPTION 60 AND OPTION 43 ..................................................................... 34-91
34.2 DHCP OPTION 60 AND OPTION 43 CONFIGURATION TASK LIST ....................................................... 34-91
34.3 DHCPV6 OPTION 60 AND OPTION 43 EXAMPLE.............................................................................. 34-92
34.4 DHCP OPTION 60 AND OPTION 43 TROUBLESHOOTING .................................................................. 34-93
CHAPTER 35 DHCPV6 OPTIONS 37, 38 ......................................................................35-1
35.1 INTRODUCTION TO DHCPV6 OPTIONS 37, 38.................................................................................... 35-1
35.2 DHCPV6 OPTIONS 37, 38 CONFIGURATION TASK LIST...................................................................... 35-2
35.3 DHCPV6 OPTIONS 37, 38 EXAMPLES .............................................................................................. 35-8 35.3.1 DHCPv6 Snooping options 37, 38 Example ....................................................................... 35-8 35.3.2 DHCPv6 Relay option37, 38 Example .............................................................................. 35-10
35.4 DHCPV6 OPTIONS 37, 38 TROUBLESHOOTING............................................................................... 35-11
CHAPTER 36 DHCP SNOOPING CONFIGURATION .................................................36-13
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36.1 INTRODUCTION TO DHCP SNOOPING.............................................................................................. 36-13
36.2 DHCP SNOOPING CONFIGURATION TASK SEQUENCE...................................................................... 36-14
36.3 DHCP SNOOPING TYPICAL APPLICATION........................................................................................ 36-19
36.4 DHCP SNOOPING TROUBLESHOOTING HELP .................................................................................. 36-20 36.4.1 Monitor and Debug Information ........................................................................................ 36-20 36.4.2 DHCP Snooping Troubleshooting Help............................................................................. 36-20
CHAPTER 37 DHCP SNOOPING OPTION 82 CONFIGURATION..............................37-21
37.1 INTRODUCTION TO DHCP SNOOPING OPTION 82 ............................................................................ 37-21 37.1.1 DHCP Option 82 Message Structure ................................................................................ 37-21 37.1.2 DHCP Snooping Option 82 Working Mechanism ............................................................. 37-22
37.2 DHCP SNOOPING OPTION 82 CONFIGURATION TASK LIST .............................................................. 37-23
37.3 DHCP SNOOPING OPTION 82 APPLICATION EXAMPLES................................................................... 37-24
37.4 DHCP SNOOPING OPTION 82 TROUBLESHOOTING.......................................................................... 37-25
CHAPTER 38 IPV4 MULTICAST PROTOCOL ............................................................38-26
38.1 IPV4 MULTICAST PROTOCOL OVERVIEW ......................................................................................... 38-26 38.1.1 Introduction to Multicast .................................................................................................... 38-26 38.1.2 Multicast Address .............................................................................................................. 38-27 38.1.3 IP Multicast Packet Transmission ..................................................................................... 38-28 38.1.4 IP Multicast Application ..................................................................................................... 38-29
38.2 DCSCM........................................................................................................................................ 38-29 38.2.1 Introduction to DCSCM ..................................................................................................... 38-29 38.2.2 DCSCM Configuration Task List........................................................................................ 38-30 38.2.3 DCSCM Configuration Examples...................................................................................... 38-33 38.2.4 DCSCM Troubleshooting .................................................................................................. 38-34
38.3 IGMP SNOOPING........................................................................................................................... 38-34 38.3.1 Introduction to IGMP Snooping......................................................................................... 38-34 38.3.2 IGMP Snooping Configuration Task List ........................................................................... 38-35 38.3.3 IGMP Snooping Examples ................................................................................................ 38-37 38.3.4 IGMP Snooping Troubleshooting ...................................................................................... 38-40
CHAPTER 39 IPV6 MULTICAST PROTOCOL ............................................................39-41
39.1 MLD SNOOPING ............................................................................................................................ 39-41 39.1.1 Introduction to MLD Snooping .......................................................................................... 39-41 39.1.2 MLD Snooping Configuration Task ................................................................................... 39-41 39.1.3 MLD Snooping Examples ................................................................................................. 39-43 39.1.4 MLD Snooping Troubleshooting........................................................................................ 39-46
CHAPTER 40 MULTICAST VLAN ...............................................................................40-47
40.1 INTRODUCTIONS TO MULTICAST VLAN ........................................................................................... 40-47
40.2 MULTICAST VLAN CONFIGURATION TASK LIST ............................................................................... 40-47
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40.3 MULTICAST VLAN EXAMPLES........................................................................................................ 40-48
CHAPTER 41 ACL CONFIGURATION ........................................................................41-51
41.1 INTRODUCTION TO ACL.................................................................................................................. 41-51 41.1.1 Access-list ......................................................................................................................... 41-51 41.1.2 Access-group .................................................................................................................... 41-51 41.1.3 Access-list Action and Global Default Action..................................................................... 41-51
41.2 ACL CONFIGURATION TASK LIST.................................................................................................... 41-52
41.3 ACL EXAMPLE .............................................................................................................................. 41-66
41.4 ACL TROUBLESHOOTING............................................................................................................... 41-71
CHAPTER 42 802.1X CONFIGURATION ....................................................................42-73
42.1 INTRODUCTION TO 802.1X.............................................................................................................. 42-73 42.1.1 The Authentication Structure of 802.1x ............................................................................. 42-73 42.1.2 The Work Mechanism of 802.1x ....................................................................................... 42-75 42.1.3 The Encapsulation of EAPOL Messages .......................................................................... 42-76 42.1.4 The Encapsulation of EAP Attributes ................................................................................ 42-78 42.1.5 The Authentication Methods of 802.1x.............................................................................. 42-79 42.1.6 The Extension and Optimization of 802.1x ....................................................................... 42-84 42.1.7 The Features of VLAN Allocation...................................................................................... 42-85
42.2 802.1X CONFIGURATION TASK LIST ................................................................................................ 42-86
42.3 802.1X APPLICATION EXAMPLE...................................................................................................... 42-90 42.3.1 Examples of Guest Vlan Applications ............................................................................... 42-90 42.3.2 Examples of IPv4 Radius Applications.............................................................................. 42-93 42.3.3 Examples of IPv6 Radius Application ............................................................................... 42-94
42.4 802.1X TROUBLESHOOTING ........................................................................................................... 42-95
CHAPTER 43 THE NUMBER LIMITATION FUNCTION OF MAC AND IP IN PORT, VLAN CONFIGURATION........................................................................................................43-96
43.1 INTRODUCTION TO THE NUMBER LIMITATION FUNCTION OF MAC AND IP IN PORT, VLAN 錯誤! 尚未定義書
籤。
43.2 THE NUMBER LIMITATION FUNCTION OF MAC AND IP IN PORT, VLAN CONFIGURATION TASK SEQUENCE
............................................................................................................................................................. 43-97
43.3 THE NUMBER LIMITATION FUNCTION OF MAC AND IP IN PORT, VLAN TYPICAL EXAMPLES............. 43-100
43.4 THE NUMBER LIMITATION FUNCTION OF MAC AND IP IN PORT, VLAN TROUBLESHOOTING HELP.... 43-101
CHAPTER 44 OPERATIONAL CONFIGURATION OF AM FUNCTION ....................44-102
44.1 INTRODUCTION TO AM FUNCTION ................................................................................................. 44-102
44.2 AM FUNCTION CONFIGURATION TASK LIST ................................................................................... 44-102
44.3 AM FUNCTION EXAMPLE.............................................................................................................. 44-104
44.4 AM FUNCTION TROUBLESHOOTING .............................................................................................. 44-105
10
CHAPTER 45 SECURITY FEATURE CONFIGURATION..........................................45-106
45.1 INTRODUCTION TO SECURITY FEATURE ......................................................................................... 45-106
45.2 SECURITY FEATURE CONFIGURATION ........................................................................................... 45-106 45.2.1 Prevent IP Spoofing Function Configuration Task Sequence ......................................... 45-106 45.2.2 Prevent TCP Unauthorized Label Attack Function Configuration Task Sequence ......... 45-107 45.2.3 Anti Port Cheat Function Configuration Task Sequence................................................. 45-107 45.2.4 Prevent TCP Fragment Attack Function Configuration Task Sequence ......................... 45-107 45.2.5 Prevent ICMP Fragment Attack Function Configuration Task Sequence ....................... 45-108
45.3 SECURITY FEATURE EXAMPLE...................................................................................................... 45-108
CHAPTER 46 TACACS+ CONFIGURATION.............................................................46-109
46.1 INTRODUCTION TO TACACS+...................................................................................................... 46-109
46.2 TACACS+ CONFIGURATION TASK LIST ........................................................................................ 46-109
46.3 TACACS+ SCENARIOS TYPICAL EXAMPLES................................................................................. 46-110
46.4 TACACS+ TROUBLESHOOTING ....................................................................................................46-111
CHAPTER 47 RADIUS CONFIGURATION................................................................47-112
47.1 INTRODUCTION TO RADIUS......................................................................................................... 47-112 47.1.1 AAA and RADIUS Introduction........................................................................................ 47-112 47.1.2 Message structure for RADIUS....................................................................................... 47-112
47.2 RADIUS CONFIGURATION TASK LIST ........................................................................................... 47-114
47.3 RADIUS TYPICAL EXAMPLES ...................................................................................................... 47-116 47.3.1 IPv4 Radius Example...................................................................................................... 47-116 47.3.2 IPv6 RadiusExample....................................................................................................... 47-117
47.4 RADIUS TROUBLESHOOTING ...................................................................................................... 47-118
CHAPTER 48 SSL CONFIGURATION.......................................................................48-119
48.1 INTRODUCTION TO SSL................................................................................................................ 48-119 48.1.1 Basic Element of SSL ..................................................................................................... 48-120
48.2 SSL CONFIGURATION TASK LIST .................................................................................................. 48-121
48.3 SSL TYPICAL EXAMPLE ............................................................................................................... 48-122
48.4 SSL TROUBLESHOOTING ............................................................................................................. 48-123
CHAPTER 49 IPV6 SECURITY RA CONFIGURATION.............................................49-124
49.1 INTRODUCTION TO IPV6 SECURITY RA.......................................................................................... 49-124
49.2 IPV6 SECURITY RA CONFIGURATION TASK SEQUENCE.................................................................. 49-124
49.3 IPV6 SECURITY RA TYPICAL EXAMPLES....................................................................................... 49-125
49.4 IPV6 SECURITY RA TROUBLESHOOTING HELP.............................................................................. 49-126
CHAPTER 50 MAB CONFIGURATION .....................................................................50-127
11
50.1 INTRODUCTION TO MAB............................................................................................................... 50-127
50.2 MAB CONFIGURATION TASK LIST................................................................................................. 50-127
50.3 MAB EXAMPLE ........................................................................................................................... 50-129
50.4 MAB TROUBLESHOOTING............................................................................................................ 50-131
CHAPTER 51 PPPOE INTERMEDIATE AGENT CONFIGURATION ........................51-132
51.1 INTRODUCTION TO PPPOE INTERMEDIATE AGENT ......................................................................... 51-132 51.1.1 Brief Introduction to PPPoE ............................................................................................ 51-132 51.1.2 Introduction to PPPoE IA ................................................................................................ 51-132
51.2 PPPOE INTERMEDIATE AGENT CONFIGURATION TASK LIST ........................................................... 51-137
51.3 PPPOE INTERMEDIATE AGENT TYPICAL APPLICATION................................................................... 51-138
51.4 PPPOE INTERMEDIATE AGENT TROUBLESHOOTING ...................................................................... 51-141
CHAPTER 52 WEB PORTAL CONFIGURATION......................................................52-142
52.1 INTRODUCTION TO WEB PORTAL AUTHENTICATION........................................................................ 52-142
52.2 WEB PORTAL AUTHENTICATION CONFIGURATION TASK LIST.......................................................... 52-142
52.3 WEB PORTAL AUTHENTICATION TYPICAL EXAMPLE....................................................................... 52-145
52.4 WEB PORTAL AUTHENTICATION TROUBLESHOOTING ..................................................................... 52-146
CHAPTER 53 VLAN-ACL CONFIGURATION ...............................................................53-1
53.1 INTRODUCTION TO VLAN-ACL ........................................................................................................ 53-1
53.2 VLAN-ACL CONFIGURATION TASK LIST .......................................................................................... 53-1
53.3 VLAN-ACL CONFIGURATION EXAMPLE............................................................................................ 53-3
53.4 VLAN-ACL TROUBLESHOOTING...................................................................................................... 53-4
CHAPTER 54 SAVI CONFIGURATION .........................................................................54-5
54.1 INTRODUCTION TO SAVI................................................................................................................... 54-5
54.2 SAVI CONFIGURATION ..................................................................................................................... 54-5
54.3 SAVI TYPICAL APPLICATION ............................................................................................................ 54-9
54.4 SAVI TROUBLESHOOTING .............................................................................................................. 54-11
CHAPTER 55 MRPP CONFIGURATION .....................................................................55-12
55.1 INTRODUCTION TO MRPP .............................................................................................................. 55-12 55.1.1 Conception Introduction .................................................................................................... 55-12 55.1.2 MRPP Protocol Packet Types ........................................................................................... 55-13 55.1.3 MRPP Protocol Operation System.................................................................................... 55-14
55.2 MRPP CONFIGURATION TASK LIST ................................................................................................ 55-14
55.3 MRPP TYPICAL SCENARIO ............................................................................................................ 55-17
55.4 MRPP TROUBLESHOOTING............................................................................................................ 55-19
12
CHAPTER 56 ULPP CONFIGURATION ......................................................................56-20
56.1 INTRODUCTION TO ULPP ............................................................................................................... 56-20
56.2 ULPP CONFIGURATION TASK LIST ................................................................................................. 56-22
56.3 ULPP TYPICAL EXAMPLES ............................................................................................................ 56-24 56.3.1 ULPP Typical Example1.................................................................................................... 56-24 56.3.2 ULPP Typical Example2.................................................................................................... 56-26
56.4 ULPP TROUBLESHOOTING............................................................................................................. 56-27
CHAPTER 57 ULSM CONFIGURATION .....................................................................57-28
57.1 INTRODUCTION TO ULSM............................................................................................................... 57-28
57.2 ULSM CONFIGURATION TASK LIST................................................................................................. 57-29
57.3 ULSM TYPICAL EXAMPLE.............................................................................................................. 57-30
57.4 ULSM TROUBLESHOOTING............................................................................................................ 57-31
CHAPTER 58 MIRROR CONFIGURATION .................................................................58-32
58.1 INTRODUCTION TO MIRROR............................................................................................................. 58-32
58.2 MIRROR CONFIGURATION TASK LIST............................................................................................... 58-32
58.3 MIRROR EXAMPLES ....................................................................................................................... 58-33
58.4 DEVICE MIRROR TROUBLESHOOTING.............................................................................................. 58-34
CHAPTER 59 SFLOW CONFIGURATION...................................................................59-35
59.1 INTRODUCTION TO SFLOW .............................................................................................................. 59-35
59.2 SFLOW CONFIGURATION TASK LIST ................................................................................................ 59-35
59.3 SFLOW EXAMPLES......................................................................................................................... 59-37
59.4 SFLOW TROUBLESHOOTING ........................................................................................................... 59-38
CHAPTER 60 RSPAN CONFIGURATION ...................................................................60-39
60.1 INTRODUCTION TO RSPAN ............................................................................................................ 60-39
60.2 RSPAN CONFIGURATION TASK LIST .............................................................................................. 60-41
60.3 TYPICAL EXAMPLES OF RSPAN..................................................................................................... 60-42
60.4 RSPAN TROUBLESHOOTING.......................................................................................................... 60-45
CHAPTER 61 ERSPAN................................................................................................61-46
61.1 INTRODUCTION TO ERSPAN .......................................................................................................... 61-46
61.2 ERSPAN CONFIGURATION TASK LIST ............................................................................................ 61-46
61.3 TYPICAL EXAMPLES OF ERSPAN .................................................................................................. 61-47
61.4 ERSPAN TROUBLESHOOTING ....................................................................................................... 61-50
CHAPTER 62 SNTP CONFIGURATION ......................................................................62-51
13
62.1 INTRODUCTION TO SNTP ............................................................................................................... 62-51
62.2 TYPICAL EXAMPLES OF SNTP CONFIGURATION .............................................................................. 62-52
CHAPTER 63 NTP FUNCTION CONFIGURATION.....................................................63-53
63.1 INTRODUCTION TO NTP FUNCTION ................................................................................................. 63-53
63.2 NTP FUNCTION CONFIGURATION TASK LIST.................................................................................... 63-53
63.3 TYPICAL EXAMPLES OF NTP FUNCTION.......................................................................................... 63-56
63.4 NTP FUNCTION TROUBLESHOOTING............................................................................................... 63-57
CHAPTER 64 SUMMER TIME CONFIGURATION ......................................................64-58
64.1 INTRODUCTION TO SUMMER TIME ................................................................................................... 64-58
64.2 SUMMER TIME CONFIGURATION TASK SEQUENCE ........................................................................... 64-58
64.3 EXAMPLES OF SUMMER TIME ......................................................................................................... 64-58
64.4 SUMMER TIME TROUBLESHOOTING................................................................................................. 64-59
CHAPTER 65 DNSV4/V6 CONFIGURATION ..............................................................65-60
65.1 INTRODUCTION TO DNS ................................................................................................................. 65-60
65.2 DNSV4/V6 CONFIGURATION TASK LIST .......................................................................................... 65-61
65.3 TYPICAL EXAMPLES OF DNS.......................................................................................................... 65-63
65.4 DNS TROUBLESHOOTING............................................................................................................... 65-64
CHAPTER 66 MONITOR AND DEBUG .......................................................................66-66
66.1 PING ............................................................................................................................................. 66-66
66.2 PING6 ........................................................................................................................................... 66-66
66.3 TRACEROUTE ................................................................................................................................ 66-66
66.4 TRACEROUTE6 .............................................................................................................................. 66-67
66.5 SHOW ........................................................................................................................................... 66-67
66.6 DEBUG.......................................................................................................................................... 66-68
66.7 SYSTEM LOG ................................................................................................................................. 66-68 66.7.1 System Log Introduction ................................................................................................... 66-68 66.7.2 System Log Configuration................................................................................................. 66-71 66.7.3 System Log Configuration Example.................................................................................. 66-72
CHAPTER 67 RELOAD SWITCH AFTER SPECIFIED TIME ......................................67-73
67.1 INTRODUCE TO RELOAD SWITCH AFTER SPECIFIED TIME ................................................................. 67-73
67.2 RELOAD SWITCH AFTER SPECIFIED TIME TASK LIST ........................................................................ 67-73
CHAPTER 68 DEBUGGING AND DIAGNOSIS FOR PACKETS RECEIVED AND SENT BY CPU ........................................................................................................................68-74
14
15
68.1 INTRODUCTION TO DEBUGGING AND DIAGNOSIS FOR PACKETS RECEIVED AND SENT BY CPU........... 68-74
68.2 DEBUGGING AND DIAGNOSIS FOR PACKETS RECEIVED AND SENT BY CPU TASK LIST ...................... 68-74
CHAPTER 69 DYING GASP CONFIGURATION .........................................................69-75
69.1 INTRODUCTION TO DYING GASP...................................................................................................... 69-75
69.2 DYING GASP TYPICAL EXAMPLES................................................................................................... 69-75
69.3 DYING GASP TROUBLESHOOTING................................................................................................... 69-75
CHAPTER 70 POE CONFIGURATION........................................................................70-76
70.1 INTRODUCTION TO POE.................................................................................................................. 70-76
70.2 POE CONFIGURATION .................................................................................................................... 70-76
70.3 TYPICAL APPLICATION OF POE....................................................................................................... 70-78
70.4 POE TROUBLESHOOTING HELP ...................................................................................................... 70-79
Chapter 1 INTRODUCTION
Thank you for purchasing PLANET L3 Multi-Port Full Gigabit Stackable Managed Switch, SGS-6340
SERIES/SGS-6340-24P4S/SGS-6340-20S4C4X/SGS-6340-48T4S. The descriptions of these models are as
follows:
SGS-6340 SERIES Layer 3 24-Port 10/100/1000T + 4-Port 1000X SFP Stackable Managed Switch
SGS-6340-24P4S Layer 3 24-Port 10/100/1000T 802.3at PoE + 4-Port 1000X SFP Stackable Managed Switch
(370W)
SGS-6340-20S4C4X Layer 3 20-Port 100/1000X SFP + 4-Port Gigabit TP/SFP + 4-Port 10G SFP+ Stackable
Managed Switch
SGS-6340-48T4S Layer 3 48-Port 10/100/1000T + 4-Port 1000X SFP Stackable Managed Switch
The term “Managed Switch” means the Switches mentioned in this user’s manual.
1.1 Packet Contents
Open the box of the Managed Switch and carefully unpack it. The box should contain the following items:
The Managed Switch x 1
Quick Installation Guide x 1
Power Cord x 1
RJ45-to-DB9 Console Cable x 1
Rubber Feet x 4
Two Rack-mounting Brackets with Attachment
Screws
SFP Dust Caps (Please refer to table below)
x 1
SFP Dust Cap Model Name
4 SGS-6340 SERIES/24P4S/48T4S
28 SGS-6340-20S4C4X
If any of these are missing or damaged, please contact your dealer immediately; if possible, retain the carton
including the original packing material, and use them again to repack the product in case there is a need to
return it to us for repair.
1.2 Product Description
Cost-effective Layer 3 Routing Solution for Enterprise Intranet Networking
Designed for enterprises and small- and medium-sized businesses where an intranet routing network is built, PLANET SGS-6340 series, a Layer 3 Stackable Gigabit Managed Switch, provides hardware-based Layer 3 routing capability with IPv4/IPv6 static routing, RIP (Routing Information Protocol) and OSPF (Open
1-1
Shortest Path First) routing features which allow to crossover different VLANs and different IP addresses, and performs effective data traffic control for security, VoIP and video streaming applications.
Efficient IP Stacking Management The SGS-6340 series supports IP stacking function that helps network managers to easily configure up to 24 switches in the same series via one single IP address instead of connecting and setting each unit one by one.
It enables centralized management regardless of the series of switches being distributed in various locations. New switches can be flexibly added to the IP stacking group when network expands.
Layer 3 Routing Support
The SGS-6340 series enables the administrator to conveniently boost network efficiency by configuring Layer 3
static routing manually, the RIP (Routing Information Protocol) or OSPF (Open Shortest Path First) settings
automatically. The RIP can employ the hop count as a routing metric and prevent routing loops by implementing
a limit on the number of hops allowed in a path from the source to a destination. The maximum number of hops
allowed for the RIP is 15. The OSPF is an interior dynamic routing protocol for autonomous system based on
link-state. The protocol creates a link-state database by exchanging link-states among Layer 3 switches, and
then uses the Shortest Path First algorithm to generate a route table based on that database.
Abundant IPv6 Support
The SGS-6340 series provides IPv6 management and enterprise-level secure features such as SSH,
ACL, WRR and RADIUS authentication. The SGS-6340 series thus helps the enterprises to step in the IPv6 era
with the lowest investment. In addition, you don’t need to replace the network facilities when the IPv6 FTTx
edge network is built.
High Performance
The SGS-6340 series boasts a high-performance switch architecture that is capable of providing non-blocking
switch fabric and wire-speed throughput as high as 56~128Gbps, which greatly simplifies the tasks of upgrading
the LAN for catering to increasing bandwidth demands.
Robust Layer 2 Features
The SGS-6340 series can be programmed for basic switch management functions such as port speed
configuration, port aggregation, VLAN, Spanning Tree Protocol, WRR, bandwidth control and IGMP snooping.
The SGS-6340 series provides 802.1Q tagged VLAN, Q-in-Q, voice VLAN and GVRP Protocol. The VLAN
groups allowed to be on the SGS-6340 series will be maximally up to 256. By supporting port aggregation, the
SGS-6340 series allows the operation of a high-speed trunk combined with multiple ports. It enables up to 128
groups for trunking with a maximum of 8 ports for each group.
Excellent Traffic Control
The SGS-6340 series is loaded with powerful traffic management and WRR features to enhance services
offered by telecoms. The WRR functionalities include wire-speed Layer 4 traffic classifiers and bandwidth
limitation which are particularly useful for multi-tenant unit, multi-business unit, Telco, or network service
applications. It also empowers the enterprises to take full advantage of the limited network resources and
guarantees the best in VoIP and video conferencing transmission.
Powerful Security
The SGS-6340 series supports ACL policies comprehensively. The traffic can be classified by
source/destination IP addresses, source/destination MAC addresses, IP protocols, TCP/UDP, IP precedence,
time ranges and ToS. Moreover, various policies can be conducted to forward the traffic. The SGS-6340 series
also provides IEEE 802.1x port based access authentication, which can be deployed with RADIUS, to ensure
1-2
the port level security and block illegal users.
Efficient Management
For efficient management, the SGS-6340 series Managed Gigabit Switch is equipped with console, Web and
SNMP management interfaces. With its built-in Web-based management interface, the SGS-6340 series offers
an easy-to-use, platform-independent management and configuration facility. The SGS-6340 series supports
standard Simple Network Management Protocol (SNMP) and can be managed via any standard-based
management software. For text-based management, the SGS-6340 series can be accessed via Telnet and the
console port. Moreover, the SGS-6340 series offers secure remote management by supporting SSH connection
which encrypts the packet content at each session.
Flexibility and Extension Solution
The SGS-6340-20S4C4X provides twenty-four 100/1000Mbps dual speed SFP Fiber ports, four 1/10Gbps
SFP+ Fiber ports, and four 10/100/1000Mbps TP/SFP combo ports. Each of the SFP+ slots
supports Dual-Speed, 10GBASE-SR/LR or 1000BASE-SX/LX. Therefore, the administrator can flexibly choose
the suitable SFP transceiver according to not only the transmission distance, but also the transmission speed
required. The four mini-GBIC slots built in the SGS-6340-24T4S/48T4S/24P4S are compatible with
1000BASE-X and WDM SFP (Small Form-factor Pluggable) fiber-optic modules. The distance can be extended
from 550 meters (multi-mode fiber) to 10/50/70/120 kilometers (single-mode fiber or WDM fiber). They are well
suited for applications within the enterprise data centers and distributions.
AC and DC Redundant Power to Ensure Continuous Operation (SGS-6340-20S4C4X only)
The SGS-6340-20S4C4X is equipped with one 100~240V AC power supply unit and one additional -48 ~ -60V
DC power supply unit for redundant power supply installation. A redundant power system is also provided to
enhance the reliability with either AC or DC power supply unit. The redundant power system is specifically
designed to handle the demands of high-tech facilities requiring the highest power integrity. Furthermore, with
the -48 ~ -60V DC power supply implemented, the SGS-6340-20S4C4X can be applied as the telecom
level device.
Centralized Power Management for Gigabit Ethernet PoE Networking (SGS-6340-24P4S only)
To fulfill the needs of higher power required PoE network applications with Gigabit speed transmission, the
SGS-6340-24P4S features high-performance Gigabit IEEE 802.3af PoE (up to 15.4 watts) and IEEE 802.3at
PoE+ (up to 30 watts) on all ports. It perfectly meets the power requirement of PoE VoIP phone and all kinds of
PoE IP cameras such as IR, PTZ, speed dome cameras or even box type IP cameras with built-in fan and
heater.
The SGS-6340-24P4S’s PoE capabilities also help to reduce deployment costs for network devices as a result
of freeing from restrictions of power outlet locations. Power and data switching are integrated into one unit,
delivered over a single cable and managed centrally. It thus eliminates cost for additional AC wiring and reduces
installation time.
PoE Schedule for Energy Saving (SGS-6340-24P4S only)
Besides being used for IP surveillance, the SGS-6340-24P4S is certainly applicable to building any PoE
network including VoIP and wireless LAN. Under the trend of energy saving worldwide and contributing to the
environmental protection on the Earth, the SGS-6340-24P4S can effectively control the power supply besides
its capability of giving high watts power. The “PoE schedule” function helps you to enable or disable PoE power
feeding for each PoE port during specified time intervals and it is a powerful function to help SMBs or
enterprises save energy and budget
1-3
1.3 Product Features
Physical Ports
4/24/48-Port 10/100/1000BASE-T Gigabit Ethernet RJ45
4/24 1000BASE-X mini-GBIC/SFP slots, SFP type auto detection (only SGS-6340-20S4C4X
supports 100BASE-FX SFP)
4 10GBASE-SR/LR SFP+ slots, compatible with 1000BASE-SX/LX/BX SFP (SGS-6340-20S4C4X
only)
RJ45 to DB9 console interface for switch basic management and setup
Power over Ethernet (SGS-6340-24P4S only)
Complies with IEEE 802.3at Power over Ethernet Plus, end-span PSE
Backward compatible with IEEE 802.3af Power over Ethernet
Up to 24 ports of IEEE 802.3af/802.3at devices powered
Supports PoE power up to 30 watts for each PoE port
Auto detects powered device (PD)
Circuit protection prevents power interference between ports
Remote power feeding up to 100 meters
PoE management
- Total PoE power budget control
- Per port PoE function enable/disable
- PoE port power feeding priority
- Per PoE port power limitation
- PD classification detection
- PoE schedule
IP Stacking
Connects with stack member via both Gigabit TP and SFP interfaces
Single IP address management, supporting up to 24 units stacked together
IP Routing Features
Supports maximum 128 static routes and route summarization
Supports dynamic routing protocol: RIP and OSPF
Layer 2 Features
Complies with the IEEE 802.3, IEEE 802.3u, IEEE 802.3ab, IEEE 802.3z Gigabit Ethernet standard
Supports auto-negotiation and half-duplex/full-duplex modes for all 10BASE-T, 100BASE-TX and
1000BASE-T ports
Auto-MDI/MDI-X detection on each RJ45 port
Prevents packet loss flow control
- IEEE 802.3x pause frame flow control in full-duplex mode
- Back-pressure flow control in half-duplex mode
High performance Store-and-Forward architecture, broadcast storm control, port loopback detect
16K MAC address table, automatic source address learning and aging
1-4
Supports VLAN
- IEEE 802.1Q tag-based VLAN
- GVRP for dynamic VLAN management
- Up to 256 VLANs groups, out of 4041 VLAN IDs
- Provider Bridging (VLAN Q-in-Q, IEEE 802.1ad) supported
- Private VLAN Edge (PVE) supported
- GVRP protocol for Management VLAN
- Protocol-based VLAN
- MAC-based VLAN
- IP subnet VLAN
Supports Link Aggregation
- Maximum 128 trunk groups, up to 8 ports per trunk group
- IEEE 802.3ad LACP (Link Aggregation Control Protocol)
- Cisco ether-channel (static trunk)
Supports Spanning Tree Protocol
- STP, IEEE 802.1D (Classic Spanning Tree Protocol)
- RSTP, IEEE 802.1w (Rapid Spanning Tree Protocol)
- MSTP, IEEE 802.1s (Multiple Spanning Tree Protocol, spanning tree by VLAN)
- Supports BPDU & root guard
Port mirroring to monitor the incoming or outgoing traffic on a particular port (many to many)
Provides port mirror (many-to-1)
Quality of Service
8 priority queues on all switch ports
Support for strict priority and WRR (Weighted Round Robin) CoS policies
Traffic classification
- IEEE 802.1p CoS/ToS
- IPv4/IPv6 DSCP
- Port-based WRR
Strict priority and WRR CoS policies
Multicast
Supports IPv4 IGMP snooping v1, v2 and v3, IPv6 MLD v1 and v2 snooping
Querier mode support
Supports Multicast VLAN Register (MVR)
Security
IEEE 802.1x port-based network access authentication
MAC-based network access authentication
Built-in RADIUS client to co-operate with the RADIUS servers for IPv4 and IPv6
TACACS+ login users access authentication
IP-based Access Control List (ACL)
MAC-based Access Control List
Supports DHCP snooping
Supports ARP inspection
IP Source Guard prevents IP spoofing attacks
1-5
Dynamic ARP Inspection discards ARP packets with invalid MAC address to IP address binding
Management
Management IP for IPv4 and IPv6
Switch Management Interface
- Console/Telnet Command Line Interface
- Web switch management
- SNMP v1, v2c, and v3 switch management
- SSH/SSL secure access
BOOTP and DHCP for IP address assignment
Firmware upload/download via TFTP or HTTP Protocol for IPv4 and IPv6
SNTP (Simple Network Time Protocol) for IPv4 and IPv6
User privilege levels control
Syslog server for IPv4 and IPv6
Four RMON groups 1, 2, 3, 9 (history, statistics, alarms and events)
Supports ping, trace route function for IPv4 and IPv6
1.4 Product Specifications
Product SGS-6340-24T4S SGS-6340-48T4S
Hardware Specifications
Copper Ports 24 10/100/1000BASE-T RJ45
auto-MDI/MDI-X ports
48 10/100/1000BASE-T RJ45
auto-MDI/MDI-X ports
SFP/mini-GBIC Slots 4 1000BASE-X SFP interfaces
Console 1 x RJ45-to-RS232 serial port (9600, 8, N, 1)
Switch Architecture Store-and-forward
Switch Fabric 56Gbps/non-blocking 104Gbps/non-blocking
Switch Throughput 41.66Mpps 77.38Mpps
Address Table 16K MAC address table with auto learning function
Shared Data Buffer 1.5MB
Flow Control Back pressure for half-duplex
IEEE 802.3x pause frame for full-duplex
Jumbo Frame 9KB
LED
System:
PWR, SYS
Ports:
10/100/1000T RJ45 Port: LNK/ACT
1000X SFP slot: LNK/ACT
Dimensions (W x D x H) 442 x 220 x 44 mm, 1U height 442 x 280 x 44 mm, 1U height
1-6
Weight 2340g 3702g
Power Consumption 19.2 watts/65.51 BTU (maximum) 38 watts/129 BTU (maximum)
Power Requirements AC 100~240V, 50/60Hz
Management Functions
System Configuration Console, Telnet, SSH, Web browser, SNMP v1, v2c and v3
Management
Supports both IPv4 and IPv6 addressing
Supports the user IP security inspection for IPv4/IPv6 SNMP
Supports MIB and TRAP
Supports IPv4/IPv6 FTP/TFTP
Supports IPv4/IPv6 NTP
Supports RMON 1, 2, 3, 9 four groups
Supports the RADIUS authentication for IPv4/IPv6 Telnet user name and
password
Supports IPv4/IPv6 SSH
The right configuration for users to adopt RADIUS server’s shell management
Supports CLI, console, Telnet
Supports SNMP v1, v2c and v3
Supports Security IP safety net management function: avoid unlawful landing at
nonrestrictive area
Supports Syslog server for IPv4 and IPv6
Supports TACACS+
Layer 3 Functions
IP Interface Per VLAN, up to 128
Routing Protocol
IPv4/IPv6 Static routing
RIPv1/v2
OSPFv1/v2
Routing Table 128
Layer 2 Functions
Port Configuration
Port disable/enable
Auto-negotiation 10/100/1000Mbps full and half duplex mode selection
Flow control disable/enable
Bandwidth control on each port
Port loopback detect
Port Status Display each port’s speed duplex mode, link status, flow control status and
auto negotiation status
VLAN
802.1Q tagged based VLAN, up to 256 VLAN groups
802.1ad Q-in-Q (VLAN stacking)
GVRP for VLAN management
Private VLAN Edge (PVE) supported
1-7
Protocol-based VLAN
MAC-based VLAN
IP subnet VLAN
Bandwidth Control TX/RX/both
Link Aggregation IEEE 802.3ad LACP/static trunk
Supports 128 groups with 8 ports per trunk group
QoS
8 priority queues on all switch ports
Supports strict priority and Weighted Round Robin (WRR) CoS policies
Traffic classification:
- IEEE 802.1p CoS/ToS
- IPv4/IPv6 DSCP
- Port-based WRR
Multicast
IGMP v1/v2/v3 snooping
Querier mode support
MLD v1/v2 snooping
Multicast VLAN Register (MVR)
Access Control List
Supports Standard and Expanded ACL
IP-based ACL/MAC-based ACL
Time-based ACL
Up to 512 entries
Bandwidth Control At least 64Kbps step
Security
Supports MAC + port binding
IPv4/IPv6 + MAC + port binding
IPv4/IPv6 + port binding
Supports MAC filter
ARP scanning prevention
Authentication IEEE 802.1x port-based network access control
AAA authentication: TACACS+ and IPv4/IPv6 over RADIUS
SNMP MIBs
RFC 1213 MIB-II
RFC 1215 Internet Engineering Task Force
RFC 1271 RMON
RFC 1354 IP-Forwarding MIB
RFC 1493 Bridge MIB
RFC 1643 Ether-like MIB
RFC 1907 SNMP v2
RFC 2011 IP/ICMP MIB
RFC 2012 TCP MIB
RFC 2013 UDP MIB
RFC 2096 IP forward MIB
RFC 2233 if MIB
1-8
RFC 2452 TCP6 MIB
RFC 2454 UDP6 MIB
RFC 2465 IPv6 MIB
RFC 2466 ICMP6 MIB
RFC 2573 SNMP v3 notify
RFC 2574 SNMP v3 vacm
RFC 2674 Bridge MIB Extensions (IEEE 802.1Q MIB)
RFC 2674 Bridge MIB Extensions (IEEE 802.1P MIB)
Standard Conformance
Regulatory Compliance FCC Part 15 Class A, CE
Standards Compliance
IEEE 802.3 10BASE-T IEEE 802.3u 100BASE-TX IEEE 802.3z Gigabit 1000BASE-SX/LX IEEE 802.3ab Gigabit 1000BASE-T IEEE 802.3x flow control and back pressure IEEE 802.3ad port trunk with LACP IEEE 802.1D Spanning Tree Protocol IEEE 802.1w Rapid Spanning Tree Protocol IEEE 802.1s Multiple Spanning Tree Protocol IEEE 802.1p Class of Service IEEE 802.1Q VLAN tagging IEEE 802.1X port authentication network control IEEE 802.1ab LLDP RFC 768 UDP RFC 793 TFTP RFC 791 IP RFC 792 ICMP RFC 2068 HTTP RFC 1112 IGMP v1 RFC 2236 IGMP v2 RFC 3376 IGMP v3 RFC 2710 MLD v1 FRC 3810 MLD v2 RFC 2328 OSPF v2 RFC 1058 RIP v1 RFC 2453 RIP v2
Environment
Operating Temperature: 0 ~ 50 degrees C Relative Humidity: 5 ~ 90% (non-condensing)
Storage Temperature: -10 ~ 70 degrees C Relative Humidity: 5 ~ 90% (non-condensing)
Product SGS-6340-24P4S
Hardware Specifications
Copper Ports 24 10/100/1000BASE-T RJ45 auto-MDI/MDI-X ports
SFP/mini-GBIC Slots 4 1000BASE-X SFP interfaces
PoE Injector Port 24 ports with 802.3at/af PoE injector function with port-1 to port-24
1-9
Console 1 x RJ45-to-RS232 serial port (9600, 8, N, 1)
Switch Architecture Store-and-forward
Switch Fabric 56Gbps/non-blocking
Switch Throughput 41.66Mpps
Address Table 16K MAC address table with auto learning function
Shared Data Buffer 1.5MB
Flow Control Back pressure for half-duplex
IEEE 802.3x pause frame for full-duplex
Jumbo Frame 9KB
LED
System:
PWR, SYS
Ports:
10/100/1000T RJ45 Port: Button off: LNK/ACT, Button on: PoE In-Use
1000X SFP slot: LNK/ACT
Dimensions (W x D x H) 442 x 330 x 44 mm, 1U height
Weight 4503g
Power Consumption 449 watts/1532.05 BTU (maximum)
Power Requirements AC 100~240V, 50/60Hz
Fan 3
Power over Ethernet
PoE Standard IEEE 802.3af/802.3at PoE+ PSE
PoE Power Supply Type End-span
PoE Power Output Per port 54V DC, 33 watts (max.)
Power Pin Assignment 1/2(+), 3/6(-)
PoE Power Budget 370 watts (max.)
PoE Ability PD @ 9 watts 24 units
PoE Ability PD @ 15 watts 24 units
PoE Ability PD @ 30 watts 12 units
Management Functions
System Configuration Console, Telnet, SSH, Web browser, SNMP v1, v2c and v3
Management
Supports both IPv4 and IPv6 addressing
Supports the user IP security inspection for IPv4/IPv6 SNMP
Supports MIB and TRAP
Supports IPv4/IPv6 FTP/TFTP
Supports IPv4/IPv6 NTP
Supports RMON 1, 2, 3, 9 four groups
Supports the RADIUS authentication for IPv4/IPv6 Telnet user name and
password
1-10
Supports IPv4/IPv6 SSH
The right configuration for users to adopt RADIUS server’s shell management
Supports CLI, console, Telnet
Supports SNMP v1, v2c and v3
Supports Security IP safety net management function: avoid unlawful landing at
nonrestrictive area
Supports Syslog server for IPv4 and IPv6
Supports TACACS+
Layer 3 Functions
IP Interface Per VLAN, up to 128
Routing Protocol Static routing, RIP and OSPF
Routing Table 128
Layer 2 Functions
Port Configuration
Port disable/enable
Auto-negotiation 10/100/1000Mbps full and half duplex mode selection
Flow control disable/enable
Bandwidth control on each port
Port loopback detect
Port Status Display each port’s speed duplex mode, link status, flow control status and
auto negotiation status
VLAN
802.1Q tagged based VLAN, up to 256 VLAN groups
802.1ad Q-in-Q (VLAN stacking)
GVRP for VLAN management
Private VLAN Edge (PVE) supported
Protocol-based VLAN
MAC-based VLAN
IP subnet VLAN
Bandwidth Control TX/RX/both
Link Aggregation IEEE 802.3ad LACP/static trunk
Supports 128 groups with 8 ports per trunk group
QoS
8 priority queues on all switch ports
Supports strict priority and Weighted Round Robin (WRR) CoS policies
Traffic classification:
- IEEE 802.1p CoS/ToS
- IPv4/IPv6 DSCP
- Port-based WRR
Multicast
IGMP v1/v2/v3 snooping
Querier mode support
MLD v1/v2 snooping
1-11
Querier mode support
Multicast VLAN Register (MVR)
Access Control List
Supports Standard and Expanded ACL
IP-based ACL/MAC-based ACL
Time-based ACL
Up to 512 entries
Bandwidth Control At least 64Kbps step
Security
Supports MAC + port binding
IPv4/IPv6 + MAC + port binding
IPv4/IPv6 + port binding
Supports MAC filter
ARP scanning prevention
Authentication IEEE 802.1x port-based network access control
AAA authentication: TACACS+ and IPv4/IPv6 over RADIUS
SNMP MIBs
RFC 1213 MIB-II
RFC 1215 Internet Engineering Task Force
RFC 1271 RMON
RFC 1354 IP-Forwarding MIB
RFC 1493 Bridge MIB
RFC 1643 Ether-like MIB
RFC 1907 SNMP v2
RFC 2011 IP/ICMP MIB
RFC 2012 TCP MIB
RFC 2013 UDP MIB
RFC 2096 IP forward MIB
RFC 2233 if MIB
RFC 2452 TCP6 MIB
RFC 2454 UDP6 MIB
RFC 2465 IPv6 MIB
RFC 2466 ICMP6 MIB
RFC 2573 SNMP v3 notify
RFC 2574 SNMP v3 vacm
RFC 2674 Bridge MIB Extensions
Standard Conformance
Regulatory Compliance FCC Part 15 Class A, CE
Standards Compliance
IEEE 802.3 10BASE-T
IEEE 802.3u 100BASE-TX
IEEE 802.3z Gigabit 1000BASE-SX/LX
IEEE 802.3ab Gigabit 1000BASE-T
IEEE 802.3x flow control and back pressure
1-12
IEEE 802.3ad port trunk with LACP
IEEE 802.1D Spanning Tree Protocol
IEEE 802.1w Rapid Spanning Tree Protocol
IEEE 802.1s Multiple Spanning Tree Protocol
IEEE 802.1p Class of Service
IEEE 802.1Q VLAN tagging
IEEE 802.1X port authentication network control
IEEE 802.1ab LLDP
IEEE 802.3af Power over Ethernet
IEEE 802.3at Power over Ethernet PLUS
RFC 768 UDP
RFC 793 TFTP
RFC 791 IP
RFC 792 ICMP
RFC 2068 HTTP
RFC 1112 IGMP v1
RFC 2236 IGMP v2
RFC 3376 IGMP v3
RFC 2710 MLD v1
FRC 3810 MLD v2
RFC 2328 OSPF v2
RFC 1058 RIP v1
RFC 2453 RIP v2
Environment
Operating Temperature: 0 ~ 50 degrees C Relative Humidity: 5 ~ 90% (non-condensing)
Storage Temperature: -10 ~ 70 degrees C Relative Humidity: 5 ~ 90% (non-condensing)
Product SGS-6340-20S4C4X
Hardware Specifications
Copper Ports 4 10/100/1000BASE-T RJ45 auto-MDI/MDI-X ports, shared with port-21 to
port-24
SFP/mini-GBIC Slots 24 100/1000BASE-X SFP interfaces
Compatible with 100BASE-FX SFP transceiver
SFP+ Slots 4 10GBASE-SR/LR SFP+ interface (port-25 to port-28)
Compatible with 1000BASE-SX/LX/BX SFP transceiver
Console 1 x RJ45-to-RS232 serial port (9600, 8, N, 1)
Switch Architecture Store-and-forward
Switch Fabric 128Gbps/non-blocking
1-13
Switch Throughput 95.24Mpps
Address Table 16K MAC address table with auto learning function
Shared Data Buffer 1.5MB
Flow Control Back pressure for half-duplex
IEEE 802.3x pause frame for full-duplex
Jumbo Frame 9KB
LED
System:
PWR, SYS
Ports:
10/100/1000T RJ45 Port: LNK/ACT
100/1000X SFP Slot: LNK/ACT
1/10G SFP+ Slot: LNK/ACT
Dimensions (W x D x H) 442 x 220 x 44 mm, 1U height
Weight 2821g
Power Consumption 54.5 watts/185.96 BTU (maximum)
Power Requirements AC 100~240V, 50/60Hz
DC -48 ~ -60V
Fan 2
Management Function
System Configuration Console, Telnet, SSH, Web browser, SNMP v1, v2c and v3
Management
Supports both IPv4 and IPv6 addressing
Supports the user IP security inspection for IPv4/IPv6 SNMP
Supports MIB and TRAP
Supports IPv4/IPv6 FTP/TFTP
Supports IPv4/IPv6 NTP
Supports RMON 1, 2, 3, 9 four groups
Supports the RADIUS authentication for IPv4/IPv6 Telnet user name and
password
Supports IPv4/IPv6 SSH
The right configuration for users to adopt RADIUS server’s shell management
Supports CLI, console, Telnet
Supports SNMPv1, v2c and v3
Supports Security IP safety net management function: avoid unlawful landing at
non-restrictive area
Supports Syslog server for IPv4 and IPv6
Supports TACACS+
Layer 3 Function
IP Interface Per VLAN, up to 128
Routing Protocol IPv4/IPv6 static routing
1-14
RIPv1/v2
OSPFv1/v2
Routing Table 128
Layer 2 Function
Port Configuration
Port disable/enable
Auto-negotiation 10/100/1000Mbps full and half duplex mode selection
Flow control disable/enable
Bandwidth control on each port
Port loopback detect
Port Status Display each port’s speed duplex mode, link status, flow control status and
auto negotiation status
VLAN
802.1Q tagged based VLAN, up to 256 VLAN groups
802.1ad Q-in-Q (VLAN stacking)
GVRP for VLAN management
Private VLAN Edge (PVE) supported
Protocol-based VLAN
MAC-based VLAN
IP subnet VLAN
Bandwidth Control TX/RX/both
Link Aggregation IEEE 802.3ad LACP/static trunk
Supports 128 groups with 8 ports per trunk group
QoS
8 priority queues on all switch ports
Supports strict priority and Weighted Round Robin (WRR) CoS policies
Traffic classification:
- IEEE 802.1p CoS/ToS
- IPv4/IPv6 DSCP
- Port-based WRR
Multicast
IGMP v1/v2/v3 snooping
Querier mode support
MLD v1/v2 snooping
Querier mode support
Multicast VLAN Register (MVR)
Access Control List
Supports Standard and Expanded ACL
IP-based ACL/MAC-based ACL
Time-based ACL
Up to 512 entries
Bandwidth Control At least 64Kbps stream
Security Supports MAC + port binding
IPv4/IPv6 + MAC + port binding
1-15
IPv4/IPv6 + port binding
Supports MAC filter
ARP scanning prevention
Authentication IEEE 802.1x port-based network access control
AAA authentication: TACACS+ and IPv4/IPv6 over RADIUS
SNMP MIBs
RFC 1213 MIB-II
RFC 1215 Internet Engineering Task Force RFC 1271 RMON RFC 1354 IP-Forwarding MIB
RFC 1493 Bridge MIB RFC 1643 Ether-like MIB RFC 1907 SNMPv2
RFC 2011 IP/ICMP MIB RFC 2012 TCP MIB RFC 2013 UDP MIB
RFC 2096 IP forward MIB RFC 2233 if MIB RFC 2452 TCP6 MIB
RFC 2454 UDP6 MIB RFC 2465 IPv6 MIB RFC 2466 ICMP6 MIB
RFC 2573 SNMPv3 notification RFC 2574 SNMPv3 VACM RFC 2674 Bridge MIB Extensions
Standard Conformance
Regulatory Compliance FCC Part 15 Class A, CE
Standards Compliance
IEEE 802.3 10BASE-T
IEEE 802.3u 100BASE-TX IEEE 802.3z Gigabit 1000BASE-SX/LX IEEE 802.3ab Gigabit 1000BASE-T
IEEE 802.3ae 10Gb/s Ethernet IEEE 802.3x flow control and back pressure IEEE 802.3ad port trunk with LACP
IEEE 802.1D Spanning Tree Protocol IEEE 802.1w Rapid Spanning Tree Protocol IEEE 802.1s Multiple Spanning Tree Protocol
IEEE 802.1p Class of Service IEEE 802.1Q VLAN tagging IEEE 802.1X port authentication network control
IEEE 802.1ab LLDP RFC 768 UDP RFC 793 TFTP
RFC 791 IP RFC 792 ICMP RFC 2068 HTTP
RFC 1112 IGMP v1 RFC 2236 IGMP v2 RFC 3376 IGMP v3
RFC 2710 MLD v1 FRC 3810 MLD v2
1-16
1-17
RFC 2328 OSPF v2 RFC 1058 RIP v1
RFC 2453 RIP v2
Environment
Operating Temperature: 0 ~ 50 degrees C Relative Humidity: 5 ~ 90% (non-condensing)
Storage Temperature: -10 ~ 70 degrees C Relative Humidity: 5 ~ 90% (non-condensing)
Chapter 2 INSTALLATION
This section describes how to install your Managed Switch and make connections to the Managed Switch.
Please read the following topics and perform the procedures in the order being presented. To install your Managed
Switch on a desktop or shelf, simply complete the following steps.
In this paragraph, we will describe how to install the Managed Switch and the installation points attended to it.
2.1 Hardware Description
2.1.1 Switch Front Panel
The unit front panel provides a simple interface monitoring the switch. Figure 2-1~ Figure 2-4 shows the front panel
of the Managed Switch.
SGS-6340-24T4S Front Panel
Figure 2-1 SGS-6340-24T4S front panel
SGS-6340-48T4S Front Panel
Figure 2-2 SGS-6340-48T4S front panel
SGS-6340-24P4S Front Panel
Figure 2-3 SGS-6340-24P4S front panel
SGS-6340-20S4C4X Front Panel
Figure 2-4 SGS-6340-20S4C4X Front Panel
18
■ Gigabit TP interface
10/100/1000BASE-T Copper, RJ45 Twisted-pair: Up to 100 meters.
■ Gigabit SFP slots
100/1000BASE-X mini-GBIC slot, SFP (Small Factor Pluggable) transceiver module: From 550 meters to 2km
(multi-mode fiber), up to above 10/20/30/40/50/70/120 kilometers (single-mode fiber). Only
SGS-6340-20S4C4X supports 100BASE-FX.
■ 10 Gigabit SFP slot
10GBASE-SR/LR mini-GBIC slot, SFP (Small Factor Pluggable) Transceiver Module supports from 300
meters (Multi-mode Fiber), up to 10 kilometers (Single Mode Fiber)
■ Console Port
The console port is a RJ45 port connector. It is an interface for connecting a terminal directly. Through the
console port, it provides rich diagnostic information including IP Address setting, factory reset, port
management, link status and system setting. Users can use the attached DB9 to RJ45 console cable in the
package and connect to the console port on the device. After the connection, users can run any terminal
emulation program (Hyper Terminal, ProComm Plus, Telix, Winterm and so on) to enter the startup screen of
the device.
■ Reset button
On the front panel, the reset button is designed for rebooting the Managed Switch without turning off and on
the power.
■ DC Power Connector (SGS-6340-20S4C4X only)
The front panel of the Managed Switch contains a power switch and a DC power connector, which accepts DC
power input voltage from -48V to -60V DC. Connect the power cable to the Managed Switch at the input
terminal block.
The wire gauge for the terminal block should be in the range of 12 ~ 24 AWG.
2.1.2 LED Indications
The front panel LEDs indicate instant status of port links, data activity, system operation, stack status and system
power.
SGS-6340-24T4S LED Indication
19
Figure 2-5 SGS-6340-24T4S LED Panel
■ System
LED Color Function
Green Lights to indicate that the Switch has power. PWR
Off Power is off.
Lights to indicate the system diagnosis is completed. SYS Green
Blinks to indicate boot is enable.
■ 10/100/1000BASE-T Interfaces
LED Color Function
Lights to indicate the link through that port is successfully established
Green Blinks to indicate that the switch is actively sending or receiving data over that
port. LNK/ACT
Off No flow goes through the port.
■ SFP Interfaces
LED Color Function
Green Lights to indicate the link through that port is successfully established LNK/ACT
Off No flow goes through the port.
SGS-6340-48T4S LED Indication
Figure 2-6 SGS-6340-48P4S LED Panel
20
■ System
LED Color Function
Green Lights to indicate that the Switch has power. PWR
Off Power is off.
Lights to indicate the system diagnosis is completed. SYS Green
Blinks to indicate boot is enable.
■ 10/100/1000BASE-T Interfaces
LED Color Function
Lights to indicate the link through that port is successfully established
Green Blinks to indicate that the switch is actively sending or receiving data over that
port. LNK/ACT
Off No flow goes through the port.
■ SFP Interfaces
LED Color Function
Green Lights to indicate the link through that port is successfully established LNK/ACT
Off No flow goes through the port.
SGS-6340-24P4S LED Indication
Figure 2-7 SGS-6340-24P4S LED Panel
■ System
LED Color Function
Green Lights to indicate that the Switch has power. PWR
Off Power is off.
Lights to indicate the system diagnosis is completed. SYS Green
Blinks to indicate boot is enable.
21
■ 10/100/1000BASE-T Interfaces
LED Color Function
Lights to indicate the link through that port is successfully established
Green Blinks to indicate that the switch is actively sending or receiving data over that
port. LNK/ACT
Off No flow goes through the port.
PoE In-Use Green Lights to indicate the port is providing 54V DC in-line power.
■ SFP Interfaces
LED Color Function
Green Lights to indicate the link through that port is successfully established LNK/ACT
Off No flow goes through the port.
SGS-6340-20S4C4X LED Indication
Figure 2-8 SGS-6340-20S4C4X LED Panel
■ System
LED Color Function
Green Lights to indicate that the Switch has power. PWR
Off Power is off.
Lights to indicate the system diagnosis is completed. SYS Green
Blinks to indicate boot is enable.
■ 10/100/1000BASE-T Interfaces
LED Color Function
Lights to indicate the link through that port is successfully established LNK/ACT
Green Blinks to indicate that the switch is actively sending or receiving data over that
port.
22
Off No flow goes through the port.
■ 100/1000X SFP Interfaces
LED Color Function
Green Lights to indicate the link through that port is successfully established LNK/ACT
Off No flow goes through the port.
■ 1/10G SFP+ Interfaces
LED Color Function
Green Lights to indicate the link through that port is successfully established LNK/ACT
Off No flow goes through the port.
2.1.3 Switch Rear Panel
The rear panel of the Managed Switch indicates an AC inlet power socket, which accepts input power from 100 to
240V AC, 50-60Hz. Figure 2-9 ~ Figure 2-12 shows the rear panel of this Managed Switch.
SGS-6340-24T4S Rear Panel
Figure 2-9 Rear Panel of SGS-6340-24T4S
SGS-6340-48T4S Rear Panel
Figure 2-10 Rear Panel of SGS-6340-48T4S
SGS-6340-24P4S Rear Panel
Figure 2-11 Rear Panel of SGS-6340-24P4S
23
SGS-6340-20S4C4X Rear Panel
Figure 2-12 Rear Panel of SGS-6340-20S4C4X
■ AC Power Receptacle
For compatibility with electric service in most areas of the world, the Managed Switch’s power supply
automatically adjusts to line power in the range of 100-240VAC and 50/60 Hz.
Plug the female end of the power cord firmly into the receptacle on the rear panel of the Managed Switch. Plug
the other end of the power cord into an electric service outlet then the power will be ready.
Power Notice:
The device is a power-required device, meaning it will not work till it is powered. If your
networks should be active all the time, please consider using UPS (Uninterruptible Power
Supply) for your device. It will prevent you from network data loss or network downtime.
In some areas, installing a surge suppression device may also help to protect your
Managed Switch from being damaged by unregulated surge or current to the Switch or the
power adapter.
24
2.2 Installing the Managed Switch
This section describes how to install your Managed Switch and make connections to the Managed Switch.
Please read the following topics and perform the procedures in the order being presented. To install your Managed
Switch on a desktop or shelf, simply complete the following steps.
In this paragraph, we will describe how to install the Managed Switch and the installation points attended to it.
2.2.1 Desktop Installation
To install the Managed Switch on desktop or shelf, please follows these steps:
Step 1: Attach the rubber feet to the recessed areas on the bottom of the Managed Switch.
Step 2: Place the Managed Switch on the desktop or the shelf near an AC power source, as shown in Figure 2-13.
Figure 2-13 Place the Managed Switch on the desk
Step 3: Keep enough ventilation space between the Managed Switch and the surrounding objects.
Step 4: Connect the Managed Switch to network devices.
Connect one end of a standard network cable to the 10/100/1000 RJ45 ports on the front of the Managed
Switch. Connect the other end of the cable to the network devices such as printer servers, workstations,
routers or others.
Connection to the Managed Switch requires UTP Category 5 network cabling with RJ45
tips. For more information, please see the Cabling Specification in Appendix A.
25
Step 5: Supply power to the Managed Switch.
Connect one end of the power cable to the Managed Switch. Connect the power plug of the power
cable into a standard wall outlet. When the Managed Switch receives power, the Power LED should
remain solid Green.
2.2.2 Rack Mounting
To install the Managed Switch in a 19-inch standard rack, please follow the instructions described below.
Step 1: Place the Managed Switch on a hard flat surface, with the front panel positioned towards the front side.
Step 2: Attach the rack-mount bracket to each side of the Managed Switch with supplied screws attached to the
package. Figure 2-14 shows how to attach brackets to one side of the Managed Switch.
Figure 2-14 Attach brackets to the Managed Switch.
You must use the screws supplied with the mounting brackets. Damage caused to the
parts by using incorrect screws would invalidate the warranty.
Step 3: Secure the brackets tightly.
Step 4: Follow the same steps to attach the second bracket to the opposite side.
Step 5: After the brackets are attached to the Managed Switch, use suitable screws to securely attach the brackets
to the rack, as shown in Figure 2-15.
26
Figure 2-15 Mounting SGS-6340 series in a Rack
Step 6: Proceeds with steps 4 and 5 of session 2.2.1 Desktop Installation to connect the network cabling and
supply power to the Managed Switch.
2.2.3 Installing the SFP/SFP+ Transceiver
The sections describe how to insert an SFP/SFP+ transceiver into an SFP/SFP+ slot. The SFP/SFP+ transceivers
are hot-pluggable and hot-swappable. You can plug in and out the transceiver to/from any SFP/SFP+ port without
having to power down the Managed Switch, as the Figure 2-16 shows.
27
Figure 2-16 Plug in the SFP transceiver
Approved PLANET SFP/SFP+ Transceivers
PLANET Managed Switch supports both single mode and multi-mode SFP/SFP+ transceivers. The following list of
approved PLANET SFP/SFP+ transceivers is correct at the time of publication:
Fast Ethernet Transceiver (100BASE-X SFP)
Model Speed (Mbps) Connector Interface Fiber Mode Distance Wavelength (nm) Operating Temp.
MFB-FX 100 LC Multi Mode 2km 1310nm 0 ~ 60 degrees C
MFB-F20 100 LC Single Mode 20km 1310nm 0 ~ 60 degrees C
MFB-F40 100 LC Single Mode 40km 1310nm 0 ~ 60 degrees C
MFB-F60 100 LC Single Mode 60km 1310nm 0 ~ 60 degrees C
MFB-F120 100 LC Single Mode 120km 1550nm 0 ~ 60 degrees C
MFB-TFX 100 LC Multi Mode 2km 1310nm -40 ~ 75 degrees C
MFB-TF20 100 LC Single Mode 20km 1550nm -40 ~ 75 degrees C
Fast Ethernet Transceiver (100BASE-BX, Single Fiber Bi-directional SFP)
Model Speed (Mbps) Connector Interface Fiber Mode Distance Wavelength (TX/RX) Operating Temp.
MFB-FA20 100 WDM(LC) Single Mode 20km 1310nm/1550nm 0 ~ 60 degrees C
MFB-FB20 100 WDM(LC) Single Mode 20km 1550nm/1310nm 0 ~ 60 degrees C
MFB-TFA20 100 WDM(LC) Single Mode 20km 1310nm/1550nm -40 ~ 75 degrees C
MFB-TFB20 100 WDM(LC) Single Mode 20km 1550nm/1310nm -40 ~ 75 degrees C
MFB-TFA40 100 WDM(LC) Single Mode 40km 1310nm/1550nm -40 ~ 75 degrees C
MFB-TFB40 100 WDM(LC) Single Mode 40km 1550nm/1310nm -40 ~ 75 degrees C
Gigabit Ethernet Transceiver (1000BASE-X SFP)
Model Speed (Mbps) Connector Interface Fiber Mode Distance Wavelength (nm) Operating Temp.
MGB-GT 1000 Copper -- 100m -- 0 ~ 60 degrees C
MGB-SX 1000 LC Multi Mode 550m 850nm 0 ~ 60 degrees C
MGB-SX2 1000 LC Multi Mode 2km 1310nm 0 ~ 60 degrees C
MGB-LX 1000 LC Single Mode 10km 1310nm 0 ~ 60 degrees C
MGB-L30 1000 LC Single Mode 30km 1310nm 0 ~ 60 degrees C
MGB-L50 1000 LC Single Mode 50km 1550nm 0 ~ 60 degrees C
MGB-L70 1000 LC Single Mode 70km 1550nm 0 ~ 60 degrees C
MGB-L120 1000 LC Single Mode 120km 1550nm 0 ~ 60 degrees C
MGB-TSX 1000 LC Multi Mode 550m 850nm -40 ~ 75 degrees C
MGB-TLX 1000 LC Single Mode 10km 1310nm -40 ~ 75 degrees C
MGB-TL30 1000 LC Single Mode 30km 1310nm -40 ~ 75 degrees C
MGB-TL70 1000 LC Single Mode 70km 1550nm -40 ~ 75 degrees C
Gigabit Ethernet Transceiver (1000BASE-BX, Single Fiber Bi-directional SFP)
28
Model Speed (Mbps) Connector Interface Fiber Mode Distance Wavelength (TX/RX) Operating Temp.
MGB-LA10 1000 WDM(LC) Single Mode 10km 1310nm/1550nm 0 ~ 60 degrees C
MGB-LB10 1000 WDM(LC) Single Mode 10km 1550nm/1310nm 0 ~ 60 degrees C
MGB-LA20 1000 WDM(LC) Single Mode 20km 1310nm/1550nm 0 ~ 60 degrees C
MGB-LB20 1000 WDM(LC) Single Mode 20km 1550nm/1310nm 0 ~ 60 degrees C
MGB-LA40 1000 WDM(LC) Single Mode 40km 1310nm/1550nm 0 ~ 60 degrees C
MGB-LB40 1000 WDM(LC) Single Mode 40km 1550nm/1310nm 0 ~ 60 degrees C
MGB-LA60 1000 WDM(LC) Single Mode 60km 1310nm/1550nm 0 ~ 60 degrees C
MGB-LB60 1000 WDM(LC) Single Mode 60km 1550nm/1310nm 0 ~ 60 degrees C
MGB-TLA10 1000 WDM(LC) Single Mode 10km 1310nm/1550nm -40 ~ 75 degrees C
MGB-TLB10 1000 WDM(LC) Single Mode 10km 1550nm/1310nm -40 ~ 75 degrees C
MGB-TLA20 1000 WDM(LC) Single Mode 20km 1310nm/1550nm -40 ~ 75 degrees C
MGB-TLB20 1000 WDM(LC) Single Mode 20km 1550nm/1310nm -40 ~ 75 degrees C
MGB-TLA40 1000 WDM(LC) Single Mode 40km 1310nm/1550nm -40 ~ 75 degrees C
MGB-TLB40 1000 WDM(LC) Single Mode 40km 1550nm/1310nm -40 ~ 75 degrees C
MGB-TLA60 1000 WDM(LC) Single Mode 60km 1310nm/1550nm -40 ~ 75 degrees C
MGB-TLB60 1000 WDM(LC) Single Mode 60km 1550nm/1310nm -40 ~ 75 degrees C
10Gbps SFP+ (10G Ethernet/10GBASE)
Model Speed (Mbps) Connector Interface Fiber Mode Distance Wavelength (nm) Operating Temp.
MTB-SR 10G LC Multi Mode Up to 300m 850nm 0 ~ 60 degrees C
MTB-LR 10G LC Single Mode 10km 1310nm 0 ~ 60 degrees C
10Gbps SFP+ (10GBASE-BX, Single Fiber Bi-directional SFP)
Model Speed (Mbps) Connector Interface Fiber Mode Distance
Wavelength
(TX) Wavelength (RX) Operating Temp.
10G WDM(LC) Single Mode 20km 1270nm 1330nm 0 ~ 60 degrees C MTB-LA20
MTB-LB20 10G WDM(LC) Single Mode 20km 1330nm 1270nm 0 ~ 60 degrees C
10G WDM(LC) Single Mode 40km 1270nm 1330nm 0 ~ 60 degrees C MTB-LA40
MTB-LB40 10G WDM(LC) Single Mode 40km 1330nm 1270nm 0 ~ 60 degrees C
10G WDM(LC) Single Mode 60km 1270nm 1330nm 0 ~ 60 degrees C MTB-LA60
MTB-LB60 10G WDM(LC) Single Mode 60km 1330nm 1270nm 0 ~ 60 degrees C
It is recommended to use PLANET SFP/SFP+ on the Managed Switch. If you insert an
SFP/SFP+ transceiver that is not supported, the Managed Switch will not recognize it.
1. Before we connect the SGS-6340 series to the other network device, we have to make sure both sides of the
SFP transceivers are with the same media type, for example: 1000BASE-SX to 1000BASE-SX, 1000Bas-LX
to 1000BASE-LX.
2. Check whether the fiber-optic cable type matches with the SFP transceiver requirement.
29
To connect to 1000BASE-SX SFP transceiver, please use the multi-mode fiber cable with one side being
the male duplex LC connector type.
To connect to 1000BASE-LX SFP transceiver, please use the single-mode fiber cable with one side being
the male duplex LC connector type.
Connect the Fiber Cable
1. Insert the duplex LC connector into the SFP/SFP+ transceiver.
2. Connect the other end of the cable to a device with SFP/SFP+ transceiver installed.
3. Check the LNK/ACT LED of the SFP/SFP+ slot on the front of the Managed Switch. Ensure that the
SFP/SFP+ transceiver is operating correctly.
4. Check the Link mode of the SFP/SFP+ port if the link fails. To function with some fiber-NICs or Media
Converters, user has to set the port Link mode to “10G Force”, “1000M Force” or “100M Force”.
Remove the Transceiver Module
1. Make sure there is no network activity anymore.
2. Remove the Fiber-Optic Cable gently.
3. Lift up the lever of the MGB module and turn it to a horizontal position.
4. Pull out the module gently through the lever.
Figure 2-17: How to Pull Out the SFP/SFP+ Transceiver
Never pull out the module without lifting up the lever of the module and turning it to a
horizontal position. Directly pulling out the module could damage the module and the
SFP/SFP+ module slot of the Managed Switch.
30
Chapter 3 Switch Management
3.1 Management Options
After purchasing the switch, the user needs to configure the switch for network management. Switch provides
two management options: in-band management and out-of-band management.
3.1.1 Out-Of-Band Management
Out-of-band management is the management through Console interface. Generally, the user will use
out-of-band management for the initial switch configuration, or when in-band management is not available.
For instance, the SGS-6340 series default IP address is 192.168.0.254 or the user can try to assign a new IP
address to the switch via the Console interface to be able to access the switch through Telnet.
The procedures for managing the switch via Console interface are listed below:
Step 1: Setting up the environment:
Figure 3-1 Out-of-band Management Configuration Environment
As shown in the above, the serial port (RS232) is connected to the switch with the serial cable provided. The
table below lists all the devices used in the connection.
Device Name Description
PC machine Has functional keyboard and RS232, with terminal emulator
installed, such as Tera Term and hyper terminal.
Serial port cable One end is connected to the RS232 serial port; the other end to
the console port.
Switch Functional console port required.
Step 2： Entering the HyperTerminal
Open the HyperTerminal included in Windows after the connection established. The example below is based
on the HyperTerminal included in Windows XP.
1) Click Start menu - All Programs -Accessories -Communication - HyperTerminal.
3-1
3-2
Figure 3-2 Opening Hyper Terminal
2) Type a name for opening HyperTerminal, such as “Switch”.
Figure 3-3 Opening HyperTerminal
3) In the “Connect using” drop-list, select the RS-232 serial port used by the PC, e.g., COM1, and click “OK”.
Figure 3-4 Opening HyperTerminal
4) COM1 property appears and select “9600” for “Baud rate”, “8” for “Data bits”, “none” for “Parity checksum”,
“1” for stop bit and “none” for traffic control; or you can also click “Restore default” and click “OK”.
Figure 3-5 Opening HyperTerminal
Step 3: Entering switch CLI interface
Power on the switch and the following appears in the HyperTerminal windows, that is the CLI configuration
mode for Switch.
System is booting, please wait...
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Bootrom version: 7.1.37
Creation date: Aug 15 2014 - 16:59:42
Testing RAM...
0x10000000 RAM OK.
Loading flash:/nos.img ...
## Booting kernel from Legacy Image at 62000100 ...
Image Name: Linux-3.6.5+
Image Type: ARM Linux Kernel Image (gzip compressed)
Data Size: 11772899 Bytes = 11.2 MiB
Load Address: 60008000
Entry Point: 60008000
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
Starting kernel ...
Current time is Sun Jan 01 00:00:00 2006
SGS-6340 SERIES Series Switch Operating System
Software Version 7.0.3.5(R0102.0087)
Compiled Aug 22 12:20:28 2014
52 Ethernet/IEEE 802.3 interface(s)
Mac Addr 00-30-4f-23-45-67
Recover config from file flash:/startup.cfg
Loading startup-config ...
……
Switch>
The user can now enter commands to manage the switch. For a detailed description of the commands, please
refer to the following chapters.
3.1.2 In-band Management
In-band management refers to the management by login to the switch using Telnet, or using HTTP, or using
SNMP management software to configure the switch. In-band management enables management of the
switch for some devices attached to the switch. In the case when in-band management fails due to switch
configuration changes, out-of-band management can be used for configuring and managing the switch.
3.1.2.1 Management via Telnet 3-4
To manage the switch with Telnet, the following conditions should be met:
1) Switch has an IPv4/IPv6 address configured;
2) The host IP address (Telnet client) and the switch’s VLAN interface IPv4/IPv6 address is in the same
network segment;
3) If 2) is not met, Telnet client can connect to an IPv4/IPv6 address of the switch via other devices,
such as a router.
The switch is Layer 3 switch that can be configured with several IPv4/IPv6 addresses. The following example
assumes the shipment status of the switch where only VLAN1 exists in the system. The following describes
the steps for a Telnet client to connect to the switch’s VLAN1 interface by Telnet (with IPv4 address as an
example):
Figure 3-6 Manage the Switch by Telnet
Step 1: Configure the IP addresses for the switch and start the Telnet Server function on the switch. First is
the configuration of host IP address. This should be within the same network segment as the switch VLAN1
interface IP address. Suppose the switch VLAN1 interface IP address is 10.1.128.251/24. Then, a possible
host IP address is 10.1.128.252/24. Run “ping 10.1.128.251” from the host and verify the result. Check for
reasons if ping fails.
The IP address configuration commands for VLAN1 interface are listed below. Before in-band management is
used, the switch must be configured with an IP address by out-of-band management (i.e. Console mode). The
configuration commands are as follows (All switch configuration prompts are assumed to be “Switch”
hereafter if not otherwise specified.):
Switch#
Switch#config
Switch (config)#interface vlan 1
Switch (Config-if-Vlan1)#ip address 10.1.128.251 255.255.255.0
Switch (Config-if-Vlan1)#no shutdown
Step 2: Run Telnet Client program.
Run Telnet client program included in Windows with the specified Telnet target.
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Figure 3-7 Run telnet client program included in Windows
Step 3: Login to the switch.
Login to the Telnet configuration interface. Valid login name and password are required, otherwise, the switch
will reject Telnet access. This is the method to protect the switch from unauthorized access. As a result, when
Telnet is enabled for configuring and managing the switch, username and password for authorized Telnet
users must be configured with the following command:
username <username> privilege <privilege> [password (0|7) <password>]
To open the local authentication style with the following command: authentication line vty login local. Privilege
option must exist and just is 15. Assume an authorized user in the switch has a username of “test”, and
password of “test”, the configuration procedure should like the following:
Switch#
Switch#config
Switch (config)#username test privilege 15 password 0 test
Switch (config)#authentication line vty login local
Enter valid login name and password in the Telnet configuration interface, Telnet user will be able to enter the
switch’s CLI configuration interface. The commands used in the Telnet CLI interface after login is the same as
that in the Console interface.
Figure 3-8 Telnet Configuration Interface
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3.1.2.2 Management via HTTP
To manage the switch via HTTP, the following conditions should be met:
1) Switch has an IPv4/IPv6 address configured;
2) The host IPv4/IPv6 address (HTTP client) and the switch’s VLAN interface IPv4/IPv6 address are in
the same network segment;
3) If 2) is not met, HTTP client should connect to an IPv4/IPv6 address of the switch via other devices,
such as a router.
Similar to management the switch via Telnet, as soon as the host succeeds to ping/ping6 an IPv4/IPv6
address of the switch and to type the right login password, it can access the switch via HTTP. The
configuration list is shown below:
Step 1: Configure the IP addresses for the switch and start the HTTP server function on the switch.
For configuring the IP address on the switch through out-of-band management, see the Telnet management
chapter.
To enable the Web configuration, users should type the CLI command IP http server in the global mode as
shown below:
Switch#
Switch#config
Switch (config)#ip http server
Step 2: Run HTTP protocol on the host.
Open the Web browser on the host and type the IP address of the switch, or run directly the HTTP protocol on
the Windows. For example, the IP address of the switch is “10.1.128.251”;
Figure 3-9 Run HTTP Protocol
When accessing a switch with IPv6 address, it is recommended to use the Firefox browser with 1.5 or later
version. For example, if the IPv6 address of the switch is 3ffe:506:1:2::3, the IPv6 address of the switch
should be http://[3ffe:506:1:2::3]. Please note the address should be in the square brackets.
Step 3: Login to the switch.
Login to the Web configuration interface. Valid login name and password are required, otherwise, the switch
3-7
will reject HTTP access. This is the method to protect the switch from unauthorized access. As a result, when
Telnet is enabled for configuring and managing the switch, username and password for authorized Telnet
users must be configured with the following command:
username <username> privilege <privilege> [password (0|7) <password>]
To open the local authentication style with the following command: authentication line web login local.
Privilege option must exist and is just 15. Assume an authorized user in the switch has a username “admin”,
and password “admin”, the configuration procedure should be as follows:
Switch#
Switch#config
Switch (config)#username admin privilege 15 password 0 admin
Switch (config)#authentication line web login local
The Web login interface of SGS-6340 Series is shown below:
Figure 3-10 Web Login Interface
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Input the right username and password and then the main Web configuration interface is shown below.
Figure 3-11 Main Web Configuration Interface
When configuring the switch, the name of the switch is composed of English letters.
3.1.2.3 Manage the Switch via SNMP Network Management Software
The followings are required by SNMP network management software to manage switches:
1) IP addresses are configured on the switch;
2) The IP address of the client host and that of the VLAN interface on the switch it subordinates to
should be in the same segment;
3) If 2) is not met, the client should be able to reach an IP address of the switch through devices like
routers;
4) SNMP should be enabled.
The host with SNMP network management software should be able to ping the IP address of the switch, so
that when running, SNMP network management software will be able to find it and implement read/write
operation on it. Details about how to manage switches via SNMP network management software will not be
covered in this manual; please refer to “Simple Network Management software user manual”.
3.2 CLI Interface
The switch provides three management interfaces for users: CLI (Command Line Interface) interface, Web
interface and Simple Network Management software. We will introduce the CLI interface and Web
configuration interface in details. Web interface is familiar with CLI interface function and will not be covered.
Please refer to “Simple Network Management software user manual”.
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CLI interface is familiar to most users. As aforementioned, out-of-band management and Telnet login are all
performed through CLI interface to manage the switch.
CLI Interface is supported by Shell program, which consists of a set of configuration commands. Those
commands are categorized according to their functions in switch configuration and management. Each
category represents a different configuration mode. The Shell for the switch is described below:
Configuration Modes
Configuration Syntax
Shortcut keys
Help function
Input verification
Fuzzy match support
3.2.1 Configuration Modes
Figure 3-12 Shell Configuration Modes
3.2.1.1 User Mode
On entering the CLI interface, entering user entry system first. If as common user, it is defaulted to User Mode.
The prompt shown is “Switch>“, the symbol “>“ is the prompt for User Mode. When exit command is run
under Admin Mode, it will also return to the User Mode.
Under User Mode, no configuration to the switch is allowed; only clock time and version information of the
switch can be queried.
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3.2.1.2 Admin Mode
Admin Mode sees the following: In user entry system, if as Admin user, it is defaulted to Admin Mode. Admin
Mode prompt “Switch#” can be entered under the User Mode by running the enable command and entering
corresponding access levels admin user password, if a password has been set. Or, when exit command is run
under Global Mode, it will also return to the Admin Mode. Switch also provides a shortcut key sequence
"Ctrl+z”, this allows an easy way to exit to Admin Mode from any configuration mode (except User Mode).
Under Admin Mode, the user can query the switch configuration information, connection status and traffic
statistics of all ports; the user can further enter the Global Mode from Admin Mode to modify all configurations
of the switch. For this reason, a password must be set for entering Admin mode to prevent unauthorized
access and malicious modification to the switch.
3.2.1.3 Global Mode
Type the config command under Admin Mode to enter the Global Mode prompt “Switch(config)#”. Use the
exit command under other configuration modes such as Port Mode, VLAN mode to return to Global Mode.
The user can perform global configuration settings under Global Mode, such as MAC Table, Port Mirroring,
VLAN creation, IGMP Snooping start and STP, etc. And the user can go further to Port Mode for configuration
of all the interfaces.
Interface Mode
Use the interface command under Global Mode to enter the interface mode specified. Switch provides three
interface types: 1. VLAN interface; 2. Ethernet port; 3. port-channel, according to the three interface
configuration modes.
Interface Type Entry Operates Exit
VLAN Interface Type interface vlan <Vlan-id>
command under Global Mode.
Configure switch IPs, etc Use the exit command
to return to Global
Mode.
Ethernet Port Type interface Ethernet
<interface-list> command
under Global Mode.
Configure supported
duplex mode, speed, etc.
of Ethernet Port.
Use the exit command
to return to Global
Mode.
port-channel Type interface port-channel
<port-channel-number>
command under Global Mode.
Configure port-channel
related settings such as
duplex mode, speed, etc.
Use the exit command
to return to Global
Mode.
VLAN Mode
Using the vlan <vlan-id> command under Global Mode to enter the corresponding VLAN Mode. Under
VLAN Mode the user can configure all member ports of the corresponding VLAN. Run the exit command
to exit the VLAN Mode to Global Mode.
DHCP Address Pool Mode
Type the ip dhcp pool <name> command under Global Mode to enter the DHCP Address Pool Mode
prompt “Switch(Config-<name>-dhcp)#”. DHCP address pool properties can be configured under DHCP
Address Pool Mode. Run the exit command to exit the DHCP Address Pool Mode to Global Mode.
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ACL Mode
ACL type Entry Operates Exit
Standard IP ACL
Mode
Type ip access-list
standard command under
Global Mode.
Configure parameters
for Standard IP ACL
Mode.
Use the exit
command to return
to Global Mode.
Extended IP ACL
Mode
Type ip access-list
extended command under
Global Mode.
Configure parameters
for Extended IP ACL
Mode.
Use the exit
command to return
to Global Mode.
3.2.2 Configuration Syntax
Switch provides various configuration commands. Although all the commands are different, they all abide by
the syntax for Switch configuration commands. The general commands format of Switch is shown below:
cmdtxt <variable> {enum1 | … | enumN } [option1 | … | optionN]
Conventions: cmdtxt in bold font indicates a command keyword; <variable> indicates a variable parameter;
{enum1 | … | enumN } indicates a mandatory parameter that should be selected from the parameter set
enum1~enumN; and the square bracket ([ ]) in [option1 | … | optionN] indicate an optional parameter. There
may be combinations of “< >“, “{ }” and “[ ]” in the command line, such as [<variable>], {enum1 <variable>|
enum2}, [option1 [option2]], etc.
Here are examples for some actual configuration commands:
show version, no parameters required. This is a command with only a keyword and no parameter, just
type in the command to run.
vlan <vlan-id>, parameter values are required after the keyword.
firewall {enable | disable}, user can enter firewall enable or firewall disable for this command.
snmp-server community {ro | rw} <string>, the followings are possible:
snmp-server community ro <string>
snmp-server community rw <string>
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3.2.3 Shortcut Key Support
Switch provides several shortcut keys to facilitate user configuration, such as up, down, left, right and blank
space. If the terminal does not recognize Up and Down keys, ctrl +p and ctrl +n can be used instead.
Key(s) Function
Back Space Delete a character before the cursor, and the cursor moves back.
Up “↑” Show previous command entered. Up to ten recently entered
commands can be shown.
Down “↓” Show next command entered. When use the Up key to get previously
entered commands, you can use the Down key to return to the next
command
Left “←” The cursor moves one character to
the left.
Right “→” The cursor moves one character to
the right.
You can use the Left and
Right key to modify an
entered command.
Ctrl +p The same as Up key “↑”.
Ctrl +n The same as Down key “↓”.
Ctrl +b The same as Left key “←”.
Ctrl +f The same as Right key “→”.
Ctrl +z Return to the Admin Mode directly from the other configuration modes
(except User Mode).
Ctrl +c Break the ongoing command process, such as ping or other command
execution.
Tab When a string for a command or keyword is entered, the Tab can be
used to complete the command or keyword if there is no conflict.
3.2.4 Help Function
There are two ways in Switch for the user to access help information: the “help” command and the “?”.
Access to Help Usage and function
Help Under any command line prompt, type in “help” and press Enter will get a
brief description of the associated help system.
“?” 1． Under any command line prompt, enter “?” to get a command list of
the current mode and related brief description.
2． Enter a “?” after the command keyword with an embedded space. If
the position should be a parameter, a description of that parameter
type, scope, etc, will be returned; if the position should be a keyword,
then a set of keywords with brief description will be returned; if the
output is “<cr>“, then the command is complete, press Enter to run the
command.
3． A “?” immediately following a string. This will display all the commands
that begin with that string.
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3-14
3.2.5 Input Verification
3.2.5.1 Returned Information: Successful
All commands entered through keyboards undergo syntax check by the Shell. Nothing will be returned if the
user enters a correct command under corresponding modes and the execution is successful.
Returned Information: error
Output error message Explanation
Unrecognized command or illegal
parameter!
The entered command does not exist, or there is
error in parameter scope, type or format.
Ambiguous command At least two interpretations are possible based on
the current input.
Invalid command or parameter The command is recognized, but no valid
parameter record is found.
This command does not exist in
current mode
The command is recognized, but this command
cannot be used under current mode.
Please configure precursor
command "*" first!
The command is recognized, but the prerequisite
command has not been configured.
syntax error : missing '"' before the
end of command line!
Quotation marks are not used in pairs.
3.2.6 Fuzzy Match Support
Switch shell supports fuzzy match in searching command and keyword. Shell will recognize commands or
keywords correctly if the entered string causes no conflict.
For example:
1) For command “show interfaces status ethernet1/1”, typing “sh in status ethernet1/1” will work.
2) However, for command “show running-config”, the system will report a “> Ambiguous command!”
error if only “show r” is entered, as Shell is unable to tell whether it is “show run” or “show
running-config”. Therefore, Shell will only recognize the command if “sh ru” is entered.
Chapter 4 Basic Switch Configuration
4.1 Basic Configuration
Basic switch configuration includes commands for entering and exiting the admin mode, for
entering and exiting interface mode, for configuring and displaying the switch clock, for
displaying the version information of the switch system, etc.
Command Explanation
Normal User Mode/ Admin Mode
enable [<1-15>]
disable
The User uses enable command to step into
admin mode from normal user mode or modify
the privilege level of the users. The disable
command is for exiting admin mode.
Admin Mode
config [terminal] Enter global mode from admin mode.
Various Modes
exit
Exit current mode and enter previous mode,
such as using this command in global mode to
go back to admin mode, and back to normal
user mode from admin mode.
show privilege Show privilege of the current users.
Except User Mode/ Admin Mode
end Quit current mode and return to Admin mode
when not in User Mode/ Admin Mode.
Admin Mode
clock set <HH:MM:SS>
[YYYY.MM.DD] Set system date and time.
show version Display version information of the switch.
set default Restore to the factory default.
write Save current configuration parameters to Flash
Memory.
reload Reset the switch.
show cpu usage Show CPU usage rate.
show cpu utilization Show current CPU utilization rate.
show memory usage Show memory usage rate.
4-1
Global Mode
banner motd <LINE>
no banner motd
Configure the information displayed when the
login authentication of a Telnet or console user is
successful.
4.2 Telnet Management
4.2.1 Telnet
4.2.1.1 Introduction to Telnet
Telnet is a simple remote terminal protocol for remote login. Using Telnet, the user can login to
a remote host with its IP address of hostname from his own workstation. Telnet can send the
user’s keystrokes to the remote host and send the remote host output to the user’s screen
through TCP connection. This is a transparent service, as to the user, the keyboard and
monitor seems to be connected to the remote host directly.
Telnet employs the Client-Server mode; the local system is the Telnet client and the remote
host is the Telnet server. Switch can be either the Telnet Server or the Telnet client. When
switch is used as the Telnet server, the user can use the Telnet client program included in
Windows or other operating systems to login to switch, as described earlier in the In-band
Management section. As a Telnet server, switch allows up to 5 Telnet client TCP connections.
And as Telnet client, using telnet command under Admin Mode allows the user to login to the
other remote hosts. Switch can only establish TCP connection to one remote host. If a
connection to another remote host is desired, the current TCP connection must be dropped.
4.2.1.2 Telnet Configuration Task List
2. Configure Telnet Server
2. Telnet to a remote host from the switch.
1. Configure Telnet Server
Command Explanation
Global Mode
telnet-server enable Enable the Telnet server function in the
4-2
no telnet-server enable switch: the no command disables the
Telnet function.
username <user-name> [privilege
<privilege>] [password [0 | 7] <password>]
no username <username>
Configure user name and password of
the Telnet. The no form command
deletes the Telnet user authorization.
aaa authorization config-commands
no aaa authorization config-commands
Enable command authorization function
for the login user with VTY (login with
Telnet and SSH). The no command
disables this function. When enabling
this command and configuring command
authorization manner, it will request to
authorize when executing some
commands.
authentication securityip <ip-addr>
no authentication securityip <ip-addr>
Configure the secure IP address to login
to the switch through Telnet: the no
command deletes the authorized Telnet
secure address.
authentication securityipv6 <ipv6-addr>
no authentication securityipv6
<ipv6-addr>
Configure IPv6 security address to login
to the switch through Telnet; the no
command deletes the authorized Telnet
security address.
authentication ip access-class
{<num-std>|<name>}
no authentication ip access-class
Binding standard IP ACL protocol to login
with Telnet/SSH/Web; the no form
command will cancel the binding ACL.
authentication ipv6 access-class
{<num-std>|<name>}
no authentication ipv6 access-class
Binding standard IPv6 ACL protocol to
login with Telnet/SSH/Web; the no form
command will cancel the binding ACL.
authentication line {console | vty | web}
login method1 [method2 …]
no authentication line {console | vty | web}
login
Configure authentication method list with
Telnet.
authentication enable method1
[method2 …]
no authentication enable
Configure the enable authentication
method list.
authorization line {console | vty | web}
exec method1 [method2 …]
no authorization line {console | vty | web}
exec
Configure the authorization method list
with Telnet.
4-3
authorization line vty command <1-15>
{local | radius | tacacs} (none|)
no authorization line vty command <1-15>
Configure command authorization
manner and authorization selection
priority of login user with VTY (login with
Telnet and SSH). The no command
recovers to be default manner.
accounting line {console | vty} command
<1-15> {start-stop | stop-only | none}
method1 [method2…]
no accounting line {console | vty}
command <1-15>
Configure the accounting method list.
Admin Mode
terminal monitor
terminal no monitor
Display debug information for Telnet
client login to the switch; the no
command disables the debug
information.
show users
Show the user information who logs in
through Telnet or SSH. It includes line
number, user name and user IP.
clear line vty <0-31>
Delete the logged user information on the
appointed line; force user to get down the
line who logs in through Telnet or SSH.
2. Telnet to a remote host from the switch
Command Explanation
Admin Mode
telnet [vrf <vrf-name>] {<ip-addr> |
<ipv6-addr> | host <hostname>} [<port>]
Login to a remote host with the Telnet
client included in the switch.
4.2.2 SSH
4.2.2.1 Introduction to SSH
SSH (Secure Shell) is a protocol which ensures a secure remote access connection to network
devices. It is based on the reliable TCP/IP protocol. By conducting the mechanism such as key
distribution, authentication and encryption between SSH server and SSH client, a secure
connection is established. The information transferred on this connection is protected from
4-4
being intercepted and decrypted. The switch meets the requirements of SSH2.0. It supports
SSH2.0 client software such as SSH Secure Client and putty. Users can run the above
software to manage the switch remotely.
The switch presently supports RSA authentication, 3DES Cryptography Protocol, SSH user
password authentication, etc.
4.2.2.2 SSH Server Configuration Task List
Command Explanation
Global Mode
ssh-server enable
no ssh-server enable
Enable SSH function on the switch; the no
command disables SSH function.
username <username> [privilege
<privilege>] [password [0 | 7]
<password>]
no username <username>
Configure the username and password of
SSH client software for logging on the
switch; the no command deletes the
username.
ssh-server timeout <timeout>
no ssh-server timeout
Configure timeout value for SSH
authentication; the no command restores
the default timeout value for SSH
authentication.
ssh-server authentication-retires
<authentication-retires>
no ssh-server authentication-retries
Configure the number of times for retrying
SSH authentication; the no command
restores the default number of times for
retrying SSH authentication.
ssh-server host-key create rsa modulus
<moduls>
Generate the new RSA host key on the
SSH server.
Admin Mode
terminal monitor
terminal no monitor
Display SSH debug information on the SSH
client side; the no command stops
displaying SSH debug information on the
SSH client side.
show crypto key Show the secret key of SSH.
rypto key clear rsa Clear the secret key of SSH.
4.2.2.3 Example of SSH Server Configuration
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Example 1:
Requirement: Enable SSH server on the switch, and run SSH2.0 client software such as
Secure shell client or putty on the terminal. Log on the switch by using the username and
password from the client.
Configure the IP address, add SSH user and enable SSH service on the switch. SSH2.0 client
can log on the switch by using the username and password to configure the switch.
Switch(config)#ssh-server enable
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 100.100.100.200 255.255.255.0
Switch(Config-if-Vlan1)#exit
Switch(config)#username test privilege 15 password 0 test
In IPv6 network, the terminal should run SSH client software which supports IPv6, such as
putty6. Users should not modify the configuration of the switch except allocating an IPv6
address for the local host.
4.3 Configure Switch IP Addresses
All Ethernet ports of switch are defaulted to Data Link layer ports and perform layer 2
forwarding. VLAN interface represents a Layer 3 interface function which can be assigned an
IP address, which is also the IP address of the switch. All VLAN interface related configuration
commands can be configured under VLAN Mode. Switch provides three IP address
configuration methods:
Manual
BOOTP
DHCP
Manual configuration of IP address is assigned to an IP address manually for the switch. In
BOOTP/DHCP mode, the switch operates as a BOOTP/DHCP client, send broadcast packets
of BOOTPRequest to the BOOTP/DHCP servers, and the BOOTP/DHCP servers assign the
address on receiving the request. In addition, switch can act as a DHCP server, and
dynamically assign network parameters such as IP addresses, gateway addresses and DNS
server addresses to DHCP clients DHCP Server configuration is detailed in later chapters.
4.3.1 Switch IP Addresses Configuration Task List
1． Enable VLAN port mode
2． Manual configuration
3． BOOTP configuration
4-6
4． DHCP configuration
1. Enable VLAN port mode
Command Explanation
Global Mode
interface vlan <vlan-id>
no interface vlan <vlan-id>
Create VLAN interface (layer 3 interface); the
no command deletes the VLAN interface.
2. Manual configuration
Command Explanation
VLAN Interface Mode
ip address <ip_address> <mask>
[secondary]
no ip address <ip_address> <mask>
[secondary]
Configure IP address of VLAN interface; the
no command deletes IP address of VLAN
interface.
ipv6 address <ipv6-address /
prefix-length> [eui-64]
no ipv6 address <ipv6-address /
prefix-length>
Configure IPv6 address, including
aggregation global unicast address, local site
address and local link address. The no
command deletes IPv6 address.
3. BOOTP configuration
Command Explanation
VLAN Interface Mode
ip bootp-client enable
no ip bootp-client enable
Enable the switch to be a BootP client and
obtain IP address and gateway address
through BootP negotiation; the no command
disables the BootP client function.
4. DHCP configuration
Command Explanation
VLAN Interface Mode
ip dhcp-client enable
no ip dhcp-client enable
Enable the switch to be a DHCP client and
obtain IP address and gateway address
through DHCP negotiation; the no command
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disables the DHCP client function.
4.4 SNMP Configuration
4.4.1 Introduction to SNMP
SNMP (Simple Network Management Protocol) is a standard network management protocol
widely used in computer network management. SNMP is an evolving protocol. SNMP v1
[RFC1157] is the first version of SNMP which is adapted by vast numbers of manufacturers for
its simplicity and easy implementation; SNMP v2c is an enhanced version of SNMP v1, which
supports layered network management; SNMP v3 strengthens the security by adding USM
(User-based Security Mode) and VACM (View-based Access Control Model).
SNMP protocol provides a simple way of exchange network management information between
two points in the network. SNMP employs a polling mechanism of message query, and
transmits messages through UDP (a connectionless transport layer protocol). Therefore it is
well supported by the existing computer networks.
SNMP protocol employs a station-agent mode. There are two parts in this structure: NMS
(Network Management Station) and Agent. NMS is the workstation on which SNMP client
program is running. It is the core on the SNMP network management. Agent is the server
software runs on the devices which need to be managed. NMS manages all the managed
objects through Agents. The switch supports Agent function.
The communication between NMS and Agent functions in Client/Server mode by exchanging
standard messages. NMS sends request and the Agent responds. There are seven types of
SNMP message:
Get-Request
Get-Response
Get-Next-Request
Get-Bulk-Request
Set-Request
Trap
Inform-Request
NMS sends queries to the Agent with Get-Request, Get-Next-Request, Get-Bulk-Request and
Set-Request messages; and the Agent, upon receiving the requests, replies with
Get-Response message. On some special situations, like network device ports are on
Up/Down status or the network topology changes, Agents can send Trap messages to NMS to
inform the abnormal events. Besides, NMS can also be set to alert to some abnormal events
by enabling RMON function. When alert events are triggered, Agents will send Trap messages
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or log the event according to the settings. Inform-Request is mainly used for inter-NMS
communication in the layered network management.
USM ensures the transfer security by well-designed encryption and authentication. USM
encrypts the messages according to the user typed password. This mechanism ensures that
the messages can’t be viewed on transmission. And USM authentication ensures that the
messages can’t be changed on transmission. USM employs DES-CBC cryptography. And
HMAC-MD5 and HMAC-SHA are used for authentication.
VACM is used to classify the users’ access permission. It puts the users with the same access
permission in the same group. Users can’t conduct the operation which is not authorized.
4.4.2 Introduction to MIB
The network management information accessed by NMS is well defined and organized in a
Management Information Base (MIB). MIB is pre-defined information which can be accessed
by network management protocols. It is in layered and structured form. The pre-defined
management information can be obtained from monitored network devices. ISO ASN.1 defines
a tree structure for MID. Each MIB organizes all the available information with this tree
structure. And each node on this tree contains an OID (Object Identifier) and a brief description
about the node. OID is a set of integers divided by periods. It identifies the node and can be
used to locate the node in an MID tree structure, shown in the figure below:
Figure 4-1 ASN.1 Tree Instance
In this figure, the OID of the object A is 1.2.1.1. NMS can locate this object through this unique
OID and gets the standard variables of the object. MIB defines a set of standard variables for
monitored network devices by following this structure.
If the variable information of Agent MIB needs to be browsed, the MIB browse software will
need to be run on the NMS. MIB in the Agent usually consists of public MIB and private MIB.
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The public MIB contains public network management information that can be accessed by all
NMS; private MIB contains specific information which can be viewed and controlled by the
support of the manufacturers.
MIB-I [RFC1156] is the first implemented public MIB of SNMP, and is replaced by MIB-II
[RFC1213]. MIB-II expands MIB-I and keeps the OID of MIB tree in MIB-I. MIB-II contains
sub-trees which are called groups. Objects in those groups cover all the functional domains in
network management. NMS obtains the network management information by visiting the MIB
of SNMP Agent.
The switch can operate as an SNMP Agent, and supports both SNMP v1/v2c and SNMP v3.
The switch supports basic MIB-II, RMON public MIB and other public MIDs such as BRIDGE
MIB. Besides, the switch supports self-defined private MIB.
4.4.3 Introduction to RMON
RMON is the most important expansion of the standard SNMP. RMON is a set of MIB
definitions, used to define standard network monitor functions and interfaces, enabling the
communication between SNMP management terminals and remote monitors. RMON provides
a highly efficient method to monitor actions inside the subnets.
MID of RMON consists of 10 groups. The switch supports the most frequently used group 1, 2,
3 and 9:
Statistics: Maintain basic usage and error statistics for each subnet monitored by the Agent.
History: Record periodical statistic samples available from Statistics.
Alarm: Allow management console users to set any count or integer for sample intervals and
alert thresholds for RMON Agent records.
Event: A list of all events generated by RMON Agent.
Alarm depends on the implementation of Event. Statistics and History display some current or
history subnet statistics. Alarm and Event provide a method to monitor any integer data
change in the network, and provide some alerts upon abnormal events (sending Trap or record
in logs).
4.4.4 SNMP Configuration
4.4.4.1 SNMP Configuration Task List
1. Enable or disable SNMP Agent server function
2. Configure SNMP community string
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3. Configure IP address of SNMP management base
4. Configure engine ID
5. Configure user
6. Configure group
7. Configure view
8. Configuring TRAP
9. Enable/Disable RMON
1. Enable or disable SNMP Agent server function
Command Explanation
Global Mode
snmp-server enabled
no snmp-server enabled
Enable the SNMP Agent function on the
switch; the no command disables the SNMP
Agent function on the switch.
2. Configure SNMP community string
Command Explanation
Global Mode
snmp-server community {ro | rw} {0 | 7}
<string> [access {<num-std>|<name>}]
[ipv6-access
{<ipv6-num-std>|<ipv6-name>}] [read
<read-view-name>] [write
<write-view-name>]
no snmp-server community <string>
[access {<num-std>|<name>}]
[ipv6-access
{<ipv6-num-std>|<ipv6-name>}]
Configure the community string for the switch;
the no command deletes the configured
community string.
3. Configure IP address of SNMP management station
Command Explanation
Global Mode
snmp-server securityip { <ipv4-address> |
<ipv6-address> }
no snmp-server securityip
{ <ipv4-address> | <ipv6-address> }
Configure IPv4/IPv6 security address which is
allowed to access the switch on the NMS; the
no command deletes the configured security
address.
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snmp-server securityip enable
snmp-server securityip disable
Enable or disable secure IP address check
function on the NMS.
4. Configure engine ID
Command Explanation
Global Mode
snmp-server engineid <engine-string>
no snmp-server engineid
Configure the local engine ID on the switch.
This command is used for SNMP v3.
5. Configure user
Command Explanation
Global Mode
snmp-server user <use-string>
<group-string> [{authPriv | authNoPriv}
auth {md5 | sha} <word>] [access
{<num-std>|<name>}] [ipv6-access
{<ipv6-num-std>|<ipv6-name>}]
no snmp-server user <user-string>
[access {<num-std>|<name>}]
[ipv6-access
{<ipv6-num-std>|<ipv6-name>}]
Add a user to an SNMP group. This command
is used to configure USM for SNMP v3.
6. Configure group
Command Explanation
Global Mode
snmp-server group <group-string>
{noauthnopriv|authnopriv|authpriv} [[read
<read-string>] [write <write-string>] [notify
<notify-string>]] [access
{<num-std>|<name>}] [ipv6-access
{<ipv6-num-std>|<ipv6-name>}]
no snmp-server group <group-string>
{noauthnopriv|authnopriv|authpriv}
[access {<num-std>|<name>}]
[ipv6-access
Set the group information on the switch. This
command is used to configure VACM for
SNMP v3.
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{<ipv6-num-std>|<ipv6-name>}]
7. Configure view
Command Explanation
Global Mode
snmp-server view <view-string>
<oid-string> {include|exclude}
no snmp-server view <view-string>
[<oid-string>]
Configure view on the switch. This command
is used for SNMP v3.
8. Configuring TRAP
Command Explanation
Global Mode
snmp-server enable traps
no snmp-server enable traps
Enable the switch to send Trap message.
This command is used for SNMP v1/v2/v3.
snmp-server host { <host-ipv4-address> |
<host-ipv6-address> } {v1 | v2c | {v3
{noauthnopriv | authnopriv | authpriv}}}
<user-string>
no snmp-server host
{ <host-ipv4-address> |
<host-ipv6-address> } {v1 | v2c | {v3
{noauthnopriv | authnopriv | authpriv}}}
<user-string>
Set the host IPv4/IPv6 address which is used
to receive SNMP Trap information. For SNMP
v1/v2, this command also configures Trap
community string; for SNMP v3, this
command also configures Trap user name
and security level. The “no” form of this
command cancels this IPv4 or IPv6 address.
snmp-server trap-source {<ipv4-address>
| <ipv6-address>}
no snmp-server trap-source
{<ipv4-address> | <ipv6-address>}
Set the source IPv4 or IPv6 address which is
used to send trap packet, the no command
deletes the configuration.
9. Enable/Disable RMON
Command Explanation
Global Mode
rmon enable
no rmon enable Enable/disable RMON.
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4.4.5 Typical SNMP Configuration Examples
The IP address of the NMS is 1.1.1.5; the IP address of the switch (Agent) is 1.1.1.9.
Scenario 1: The NMS network administrative software uses SNMP protocol to obtain data
from the switch.
The configuration on the switch is listed below:
Switch(config)#snmp-server enable
Switch(config)#snmp-server community rw private
Switch(config)#snmp-server community ro public
Switch(config)#snmp-server securityip 1.1.1.5
The NMS can use private as the community string to access the switch with read-write
permission, or use public as the community string to access the switch with read-only
permission.
Scenario 2: NMS will receive Trap messages from the switch (Note: NMS may have
community string verification for the Trap messages. In this scenario, the NMS uses a Trap
verification community string of usertrap).
The configuration on the switch is listed below:
Switch(config)#snmp-server enable
Switch(config)#snmp-server host 1.1.1.5 v1 usertrap
Switch(config)#snmp-server enable traps
Scenario 3: NMS uses SNMP v3 to obtain information from the switch.
The configuration on the switch is listed below:
Switch(config)#snmp-server
Switch(config)#snmp-server user tester UserGroup authPriv auth md5 hellotst
Switch(config)#snmp-server group UserGroup AuthPriv read max write max notify max
Switch(config)#snmp-server view max 1 include
Scenario 4: NMS wants to receive the v3Trap messages sent by the switch.
The configuration on the switch is listed below:
Switch(config)#snmp-server enable
Switch(config)#snmp-server host 10.1.1.2 v3 authpriv tester
Switch(config)#snmp-server enable traps
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Scenario 5: The IPv6 address of the NMS is 2004:1:2:3::2; the IPv6 address of the switch
(Agent) is 2004:1:2:3::1. The NMS network administrative software uses SNMP protocol to
obtain data from the switch.
The configuration on the switch is listed below:
Switch(config)#snmp-server enable
Switch(config)#snmp-server community rw private
Switch(config)#snmp-server community ro public
Switch(config)#snmp-server securityip 2004:1:2:3::2
The NMS can use private as the community string to access the switch with read-write
permission, or use public as the community string to access the switch with read-only
permission.
Scenario 6: NMS will receive Trap messages from the switch (Note: NMS may have
community string verification for the Trap messages. In this scenario, the NMS uses a Trap
verification community string of usertrap).
The configuration on the switch is listed below:
Switch(config)#snmp-server host 2004:1:2:3::2 v1 usertrap
Switch(config)#snmp-server enable traps
4.4.6 SNMP Troubleshooting
When users configure the SNMP, the SNMP server may fail to run properly due to physical
connection failure and wrong configuration, etc. Users can troubleshoot the problems by
following the guide below:
Good condition of the physical connection.
Interface and datalink layer protocol is Up (use the “show interface” command), and the
connection between the switch and host can be verified by ping (use “ping” command).
The switch enabled SNMP Agent server function (use “snmp-server” command)
Secure IP for NMS (use “snmp-server securityip” command) and community string (use
“snmp-server community” command) are correctly configured, as any of them fails,
SNMP will not be able to communicate with NMS properly.
If Trap function is required, remember to enable Trap (use “snmp-server enable traps”
command). And remember to properly configure the target host IP address and
community string for Trap (use “snmp-server host” command) to ensure Trap message
can be sent to the specified host.
If RMON function is required, RMON must be enabled first (use “rmon enable”
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command).
Use “show snmp” command to verify sent and received SNMP messages; Use “show
snmp status” command to verify SNMP configuration information; Use “debug snmp
packet” to enable SNMP debugging function and verify debug information.
If users still can’t solve the SNMP problems, Please contact our technical and service
center.
4.5 Switch Upgrade
Switch provides two ways for switch upgrade: BootROM upgrade and the TFTP/FTP upgrade
under Shell.
4.5.1 Switch System Files
The system files include system image file and boot file. The updating of the switch is to
update the two files by overwriting the old files with the new ones.
The system image files refer to the compressed files of the switch hardware drivers, and
software support program, etc, namely what we usually called the IMG update file. The IMG
file can only be saved in the FLASH with a defined name of nos.img
The boot file is for initiating the switch, namely what we usually called the ROM update file (It
can be compressed into IMG file if it is of large size.). In the switch, the boot file is allowed to
save in ROM only. Switch mandates the name of the boot file to be boot.rom.
The update method of the system image file and the boot file is the same. The switch supplies
the user with two modes of updating: 1. BootROM mode; 2. TFTP and FTP update in Shell
mode. This two update method will be explained in details in the following two sections.
4.5.2 BootROM Upgrade
There are two methods for BootROM upgrade: TFTP and FTP, which can be selected at
BootROM command settings.
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Cable
connection Console cable
connection
Figure 4-2 Typical topology for switch upgrade in BootROM mode
The upgrade procedures are listed below:
Step 1:
As shown in the figure, a PC is used as the console for the switch. A console cable is used to
connect PC to the management(MGMT) port on the switch. The PC should have FTP/TFTP
server software installed and has the image file required for the upgrade.
Step 2:
Press “ctrl+b” on switch boot up until the switch enters BootROM monitor mode. The operation
result is shown below:
[Boot]:
Step 3:
Under BootROM mode, run “setconfig” to set the IP address and mask of the switch under
BootROM mode, server IP address and mask, and select TFTP or FTP upgrade. Suppose the
switch address is 192.168.1.2, and PC address is 192.168.1.66, and select TFTP upgrade, the
configuration should like:
[Boot]: setconfig
Host IP Address: [10.1.1.1] 192.168.1.2
Server IP Address: [10.1.1.2] 192.168.1.66
FTP(1) or TFTP(2): [1] 2
Network interface configure OK.
[Boot]
Step 4:
Enable FTP/TFTP server in the PC. For TFTP, run TFTP server program; for FTP, run FTP
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server program. Before start downloading upgrade file to the switch, verify the connectivity
between the server and the switch by ping from the server. If ping succeeds, run “load”
command in the BootROM mode from the switch; if it fails, perform troubleshooting to find out
the cause. The following is the configuration for the system update image file.
[Boot]: load nos.img
Loading...
Loading file ok!
Step 5:
Execute write nos.img in BootROM mode. The following saves the system update image file.
[Boot]: write nos.img
File nos.img exists, overwrite? (Y/N)?[N] y
Writing nos.img.....................................................
Write nos.img OK.
[Boot]:
Step 6:
The following update file boot.rom, the basic environment is the same as Step 4.
[Boot]: load boot.rom
Loading…
Loading file ok!
Step 7:
Execute write boot.rom in BootROM mode. The following saves the update file.
[Boot]: write boot.rom
File boot.rom exists, overwrite? (Y/N)?[N] y
Writing boot.rom………………………………………
Write boot.rom OK.
[Boot]:
Step 8:
After successful upgrade, execute run or reboot command in BootROM mode to return to CLI
configuration interface.
[Boot]: run（or reboot）
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Other commands in BootROM mode
1. DIR command
Used to list existing files in the FLASH.
[Boot]: dir
boot.rom 327,440 1900-01-01 00:00:00 --SH
boot.conf 83 1900-01-01 00:00:00 --SH
nos.img 2,431,631 1980-01-01 00:21:34 ----
startup-config 2,922 1980-01-01 00:09:14 ----
temp.img 2,431,631 1980-01-01 00:00:32 ----
2. CONFIG RUN command
Used to set the IMAGE file to run upon system start-up, and the configuration file to run upon
configuration recovery.
[Boot]: config run
Boot File: [nos.img] nos.img
Config File: [boot.conf]
4.5.3 FTP/TFTP Upgrade
4.5.3.1 Introduction to FTP/TFTP
FTP (File Transfer Protocol)/TFTP (Trivial File Transfer Protocol) are both file transfer
protocols that belong to the fourth layer (application layer) of the TCP/IP protocol stack, used
for transferring files between hosts, hosts and switches. Both of them transfer files in a
client-server model. Their differences are listed below.
FTP builds upon TCP to provide reliable connection-oriented data stream transfer service.
However, it does not provide file access authorization and uses simple authentication
mechanism (transfers username and password in plain text for authentication). When using
FTP to transfer files, two connections need to be established between the client and the server:
a management connection and a data connection. A transfer request should be sent by the
FTP client to establish management connection on port 21 in the server, and negotiate a data
connection through the management connection.
There are two types of data connections: active connection and passive connection. In active
connection, the client transmits its address and port number for data transmission to the server,
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the management connection maintains until data transfer is complete. Then, using the address
and port number provided by the client, the server establishes data connection on port 20 (if
not engaged) to transfer data; if port 20 is engaged, the server automatically generates some
other port numbers to establish data connection.
In passive connection, the client, through management connection, notify the server to
establish a passive connection. The server then creates its own data listening port and informs
the client about the port, and the client establishes data connection to the specified port.
As data connection is established through the specified address and port, there is a third party
to provide data connection service.
TFTP builds upon UDP, providing unreliable data stream transfer service with no user
authentication or permission-based file access authorization. It ensures correct data
transmission by sending and acknowledging mechanism and retransmission of time-out
packets. The advantage of TFTP over FTP is that it is a simple and low overhead file transfer
service.
Switch can operate as either FTP/TFTP client or server. When switch operates as an
FTP/TFTP client, configuration files or system files can be downloaded from the remote
FTP/TFTP servers (can be hosts or other switches) without affecting its normal operation. And
file list can also be retrieved from the server in FTP client mode. Of course, switch can also
upload current configuration files or system files to the remote FTP/TFTP servers (can be
hosts or other switches). When switch operates as an FTP/TFTP server, it can provide file
upload and download service for authorized FTP/TFTP clients, as file list service as FTP
server.
Here are some terms frequently used in FTP/TFTP.
ROM: Short for EPROM is erasable read-only memory. EPROM is repalced by FLASH
memory in switch.
SDRAM: RAM memory in the switch is used for system software operation and configuration
sequence storage.
FLASH: Flash memory is used to save system file and configuration file.
System file: including system image file and boot file.
System image file: Refers to the compressed file for switch hardware driver and software
support program, usually refer to as IMAGE upgrade file. In switch, the system image file is
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allowed to save in FLASH only. Switch mandates the name of system image file to be
uploaded via FTP in Global Mode to be nos.img, other IMAGE system files will be rejected.
Boot file: Refers to the file initializes the switch, also referred to as the ROM upgrade file
(Large size file can be compressed as IMAGE file). In switch, the boot file is allowed to save in
ROM only. Switch mandates the name of the boot file to be boot.rom.
Configuration file: Including start up configuration file and running configuration file. The
distinction between startup configuration file and running configuration file can facilitate the
backup and update of the configurations.
Startup configuration file: Refers to the configuration sequence used in switch startup.
Startup configuration file is stored in nonvolatile storage, corresponding to the so-called
configuration save. If the device does not support CF, the configuration file will be stored in
FLASH only. If the device supports CF, the configuration file will be stored in FLASH or CF. If
the device supports multi-config file, the name of the configuration file will be .cfg file (The
default is startup.cfg.). If the device does not support multi-config file, the name of the startup
configuration file will be startup-config.
Running configuration file: Refers to the running configuration sequence used in the switch.
In the switch, the running configuration file stores in the RAM. In the current version, the
running configuration sequence running-config can be saved from the RAM to FLASH by write
command or copy running-config startup-config command, so that the running
configuration sequence becomes the startup configuration file, which is called configuration
save. To prevent illicit file upload and easier configuration, switch mandates the name of
running configuration file to be running-config.
Factory configuration file: The configuration file shipped with switch named factory-config.
Run set default and write and restart the switch, and factory configuration file will be loaded to
overwrite current startup configuration file.
4.5.3.2 FTP/TFTP Configuration
The configurations of switch as FTP and TFTP clients are almost the same, so the
configuration procedures for FTP and TFTP are described together in this manual.
4.5.3.2.1 FTP/TFTP Configuration Task List
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1. FTP/TFTP client configuration
（1） Upload/download the configuration file or system file.
（2） For FTP client, server file list can be checked.
2. FTP server configuration
（1） Start FTP server
（2） Configure FTP login username and password
（3） Modify FTP server connection idle time
（4） Shut down FTP server
3. TFTP server configuration
（1） Start TFTP server
（2） Configure TFTP server connection idle time
（3） Configure retransmission times before timeout for packets without
acknowledgement
（4） Shut down TFTP server
1. FTP/TFTP client configuration
（1）FTP/TFTP client upload/download file
Command Explanation
Admin Mode
copy <source-url> <destination-url>
[ascii | binary] FTP/TFTP client upload/download file.
（2）For FTP client, server file list can be checked.
Admin Mode
ftp-dir <ftpServerUrl>
For FTP client, server file list can be
checked. FtpServerUrl format looks like: ftp:
//user: password@IPv4|IPv6 Address.
2. FTP server configuration
（1）Start FTP server
Command Explanation
Global Mode
ftp-server enable
no ftp-server enable
Start FTP server, the no command shuts down
FTP server and prevents FTP user from logging
in.
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（2）Configure FTP login username and password
Command Explanation
Global Mode
ip ftp username <username>
password [0 | 7] <password>
no ip ftp username<username>
Configure FTP login username and password;
this no command will delete the username and
password.
（3）Modify FTP server connection idle time
Command Explanation
Global Mode
ftp-server timeout <seconds> Set connection idle time.
3. TFTP server configuration
（1）Start TFTP server
Command Explanation
Global Mode
tftp-server enable
no tftp-server enable
Start TFTP server, the no command shuts down
TFTP server and prevents TFTP user from
logging in.
（2）Modify TFTP server connection idle time
Command Explanation
Global Mode
tftp-server retransmission-timeout
<seconds>
Set maximum retransmission time within timeout
interval.
（3）Modify TFTP server connection retransmission time
Command Explanation
Global Mode
tftp-server retransmission-number
<number> Set the retransmission time for TFTP server.
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4.5.3.3 FTP/TFTP Configuration Examples
The configuration is the same as IPv4 address or IPv6 address. The example is only for IPv4
address.
10.1.1.2
10.1.1.1
Figure 4-2 Download nos.img file as FTP/TFTP client
Scenario 1: The switch is used as FTP/TFTP client. The switch connects from one of its ports
to a computer, which is a FTP/TFTP server with an IP address of 10.1.1.1; the switch acts as a
FTP/TFTP client, the IP address of the switch management VLAN is 10.1.1.2. Download
“nos.img” file in the computer to the switch.
FTP Configuration
Computer side configuration:
Start the FTP server software on the computer and set the username “Switch”, and the
password “superuser”. Place the “12_30_nos.img” file to the appropriate FTP server directory
on the computer.
The configuration procedures of the switch are listed below:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-Vlan1)#no shut
Switch(Config-if-Vlan1)#exit
Switch(config)#exit
Switch#copy ftp: //Switch:[email protected]/12_30_nos.img nos.img
With the above commands, the switch will have the “nos.img” file in the computer downloaded
to the FLASH.
TFTP Configuration
4-24
Computer side configuration:
Start TFTP server software on the computer and place the “12_30_nos.img” file to the
appropriate TFTP server directory on the computer.
The configuration procedures of the switch are listed below:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-Vlan1)#no shut
Switch(Config-if-Vlan1)#exit
Switch(config)#exit
Switch#copy tftp: //10.1.1.1/12_30_nos.img nos.img
Scenario 2: The switch is used as FTP server. The switch operates as the FTP server and
connects from one of its ports to a computer, which is a FTP client. Transfer the “nos.img” file
in the switch to the computer and save as 12_25_nos.img.
The configuration procedures of the switch are listed below:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-Vlan1)#no shut
Switch(Config-if-Vlan1)#exit
Switch(config)#ftp-server enable
Switch(config)# username Admin password 0 superuser
Computer side configuration:
Login to the switch with any FTP client software, with the username “Switch” and password
“superuser”, use the command “get nos.img 12_25_nos.img” to download “nos.img” file from
the switch to the computer.
Scenario 3: The switch is used as TFTP server. The switch operates as the TFTP server and
connects from one of its ports to a computer, which is a TFTP client. Transfer the “nos.img” file
in the switch to the computer.
The configuration procedures of the switch are listed below:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-Vlan1)#no shut
Switch(Config-if-Vlan1)#exit
4-25
Switch(config)#tftp-server enable
Computer side configuration:
Login to the switch with any TFTP client software, use the “tftp” command to download
“nos.img” file from the switch to the computer.
Scenario 4: Switch acts as FTP client to view file list on the FTP server. Synchronization
conditions: The switch connects to a computer by an Ethernet port, the computer is a FTP
server with an IP address of 10.1.1.1; the switch acts as a FTP client, and the IP address of the
switch management VLAN1 interface is 10.1.1.2.
FTP Configuration:
PC side:
Start the FTP server software on the PC and set the username “Switch”, and the password
“superuser”.
Switch:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-Vlan1)#no shut
Switch(Config-if-Vlan1)#exit
Switch#copy ftp: //Switch: [email protected]
220 Serv-U FTP-Server v2.5 build 6 for WinSock ready...
331 User name okay, need password.
230 User logged in, proceed.
200 PORT Command successful.
150 Opening ASCII mode data connection for /bin/ls.
recv total = 480
nos.img
nos.rom
parsecommandline.cpp
position.doc
qmdict.zip
…(some display omitted here)
show.txt
snmp.TXT
226 Transfer complete.
4-26
4.5.3.4 FTP/TFTP Troubleshooting
4.5.3.4.1 FTP Troubleshooting
When upload/download system file with FTP protocol, the connectivity of the link must be
ensured, i.e., use the “Ping” command to verify the connectivity between the FTP client and
server before running the FTP program. If ping fails, you will need to check for appropriate
troubleshooting information to recover the link connectivity.
The following is what the message displays when files are successfully transferred.
Otherwise, please verify link connectivity and retry “copy” command again.
220 Serv-U FTP-Server v2.5 build 6 for WinSock ready...
331 User name okay, need password.
230 User logged in, proceed.
200 PORT Command successful.
nos.img file length = 1526021
read file ok
send file
150 Opening ASCII mode data connection for nos.img.
226 Transfer complete.
close ftp client.
The following is the message displays when files are successfully received. Otherwise,
please verify link connectivity and retry “copy” command again.
220 Serv-U FTP-Server v2.5 build 6 for WinSock ready...
331 User name okay, need password.
230 User logged in, proceed.
200 PORT Command successful.
recv total = 1526037
************************
write ok
150 Opening ASCII mode data connection for nos.img (1526037 bytes).
226 Transfer complete.
If the switch is an upgraded system file or system startup file through FTP, the switch
must not be restarted until “close ftp client” or “226 Transfer complete.” is displayed,
indicating upgrade is successful, otherwise, the switch may be rendered unable to start.
If the system file and system startup file upgrade through FTP fails, please try to upgrade
again or use the BootROM mode to upgrade.
4-27
4.5.3.4.2 TFTP Troubleshooting
When uploading/downloading system file with TFTP protocol, the connectivity of the link must
be ensured, i.e., use the “Ping” command to verify the connectivity between the TFTP client
and server before running the TFTP program. If ping fails, you will need to check for
appropriate troubleshooting information to recover the link connectivity.
The following is the message displayed when files are successfully transferred.
Otherwise, please verify link connectivity and retry “copy” command again.
nos.img file length = 1526021
read file ok
begin to send file, wait...
file transfers complete.
Close tftp client.
The following is the message displayed when files are successfully received. Otherwise,
please verify link connectivity and retry “copy” command again.
begin to receive file, wait...
recv 1526037
************************
write ok
transfer complete
close tftp client.
If the switch is an upgraded system file or system startup file through TFTP, the switch must
not be restarted until “close tftp client” is displayed, indicating upgrade is successful, otherwise,
the switch may be rendered unable to start. If the system file and system startup file upgrade
through TFTP fails, please try upgrading again or use the BootROM mode to upgrade.
4-28
Chapter 5 File System Operations
5.1 Introduction to File Storage Devices
File storage devices used in switches mainly include FLASH cards. As the most common
storage device, FLASH is usually used to store system image files (IMG files), system boot
files (ROM files) and system configuration files (CFG files). Flash can copy, delete, or rename
files under Shell or BootROM mode.
5.2 File System Operation Configuration Task List
1. The formatting operation of storage devices
2. The creation of sub-directories
3. The deletion of sub-directory
4. Changing the current working directory of the storage device
5. The display operation of the current working directory
6. The display operation of information about a designated file or directory
7. The deletion of a designated file in the file system
8. The renaming operation of files
9. The copying operation of files
1. The formatting operation of storage devices
Command Explanation
Admin Mode
format <device> Format the storage device.
2. The creation of sub-directories
Command Explanation
5-29
Admin Mode
mkdir <directory> Create a sub-directory in a designated
directory on a certain device.
3. The deletion of sub-directory
Command Explanation
Admin Mode
rmdir <directory> Delete a sub-directory in a designated
directory on a certain device.
4. Changing the current working directory of the storage device
Command Explanation
Admin Mode
cd <directory> Change the current working directory of the
storage device.
5. The display operation of the current working directory
Command Explanation
Admin Mode
pwd Display the current working directory.
6. The display operation of information about a designated file or directory
Command Explanation
Admin Mode
dir [WORD] Display information about a designated file or
directory on the storage device.
7. The deletion of a designated file in the file system
Command Explanation
Admin Mode
delete <file-url> Delete the designated file in the file system.
5-30
8. The renaming operation of files
Command Explanation
Admin Mode
rename <source-file-url> <dest-file> Change the name of a designated file on the
switch to a new one.
9. The copy operation of files
Command Explanation
Admin Mode
copy <source-file-url > <dest-file-url> Copy a designated file one the switch and
store it as a new one.
5.3 Typical Applications
Copy an IMG file flash:/nos.img stored in the FLASH on the boardcard, to cf:/nos-6.1.11.0.img.
The configuration of the switch is as follows:
Switch#copy flash:/nos.img flash:/nos-6.1.11.0.img
Copy flash:/nos.img to flash:/nos-6.1.11.0.img? [Y:N] y
Copyed file flash:/nos.img to flash:/nos-6.1.11.0.img.
5.4 Troubleshooting
If errors occur when users try to implement file system operations, please check whether they
are caused by the following reasons
Whether file names or paths are entered correctly.
When renaming a file, whether it is in use or the new file name is already used by an existing
file or directory
5-31
5-32
Chapter 6 Cluster Configuration
6.1 Introduction to cluster network management
Cluster network management is an in-band configuration management. Unlike CLI, SNMP and
Web Config which implement a direct management of the target switches through a
management workstation, cluster network management implements a direct management of
the target switches (member switches) through an intermediate switch (commander switch). A
commander switch can manage multiple member switches. As soon as a Public IP address is
configured in the commander switch, all the member switches which are configured with
private IP addresses can be managed remotely. This feature economizes public IP addresses
which are short of supply. Cluster network management can dynamically discover cluster
feature enabled switches (candidate switches). Network administrators can statically or
dynamically add the candidate switches to the cluster which is already established.
Accordingly, they can configure and manage the member switches through the commander
switch. When the member switches are distributed in various physical locations (such as on
the different floors of the same building), cluster network management has obvious
advantages. Moreover, cluster network management is an in-band management. The
commander switch can communicate with member switches in existing network. There is no
need to build a specific network for network management.
Cluster network management has the following features:
Save IP addresses
Simplify configuration tasks
Indifference to network topology and distance limitation
Auto detecting and auto establishing
With factory default settings, multiple switches can be managed through cluster network
management
The commander switch can upgrade and configure any member switches in the cluster
6.2 Cluster Network Management Configuration
Sequence
Cluster Network Management Configuration Sequence:
6-1
1． Enable or disable cluster function
2． Create cluster
1) Configure private IP address pool for member switches of the cluster
2) Create or delete cluster
3) Add or remove a member switch
3． Configure attributes of the cluster in the commander switch
1) Enable or disable automatically adding cluster members
2) Set automatically added members to manually added ones
3) Set or modify the time interval of keep-alive messages on switches in the cluster.
4) Set or modify the max. number of lost keep-alive messages that can be tolerated
5) Clear the list of candidate switches maintained by the switch
4． Configure attributes of the cluster in the candidate switch
1) Set the time interval of keep-alive messages of the cluster
2) Set the max. number of lost keep-alive messages that can be tolerated in the cluster
5． Remote cluster network management
1) Remote configuration management
2) Remotely upgrade member switch
3) Reboot member switch
6． Manage cluster network with web
1) Enable http
7． Manage cluster network with snmp
1) Enable snmp server
1. Enable or disable cluster
Command Explanation
Global Mode
cluster run [key <WORD>] [vid <VID>]
no cluster run
Enable or disable cluster function in
the switch.
6-2
2. Create a cluster
Command Explanation
Global Mode
cluster ip-pool <commander-ip>
no cluster ip-pool
Configure the private IP address pool
for cluster member devices.
cluster commander [<cluster_name>]
no cluster commander Create or delete a cluster.
cluster member {nodes-sn <nodes-sn> |
mac-address <mac-addr> [id <member-id> ] |
auto-to-user}
no cluster member {id <member-id> |
mac-address <mac-addr>}
Add or remove a member switch.
3. Configure attributes of the cluster in the commander switch
Command Explanation
Global Mode
cluster auto-add
no cluster auto-add
Enable or disable adding newly
discovered candidate switch to the
cluster.
cluster member auto-to-user Change automatically added
members into manually added ones.
cluster keepalive interval <second>
no cluster keepalive interval
Set the keep-alive interval of the
cluster.
cluster keepalive loss-count <int>
no cluster keepalive loss-count
Set the max. number of lost
keep-alive messages that can be
tolerated in the cluster.
Admin Mode
clear cluster nodes [nodes-sn
<candidate-sn-list> | mac-address
<mac-addr>]
Clear nodes in the list of candidate
switches maintained by the switch.
6-3
4. Configure attributes of the cluster in the candidate switch
Command Explanation
Global Mode
cluster keepalive interval <second>
no cluster keepalive interval
Set the keep-alive interval of the
cluster.
cluster keepalive loss-count <int>
no cluster keepalive loss-count
Set the max. number of lost
keep-alive messages that can be
tolerated in the clusters.
5. Remote cluster network management
Command Explanation
Admin Mode
rcommand member <member-id>
In the commander switch, this
command is used to configure and
manage member switches.
rcommand commander
In the member switch, this command
is used to configure the commander
switch.
cluster reset member [id <member-id> |
mac-address <mac-addr>]
In the commander switch, this
command is used to reset the
member switch.
cluster update member <member-id>
<src-url> <dst-filename>[ascii | binary]
In the commander switch, this
command is used to remotely
upgrade the member switch. It can
only upgrade nos.img file.
6-4
6. Manage cluster network with web
Command Explanation
Global Mode
ip http server
Enable http function in commander
switch and member switch.
Note: Ensure the http function is
enabled in member switch when
commander switch visiting member
switch by web. The commander
switch visits member switch via beat
member node in member cluster
topology.
7. Manage cluster network with snmp
Command Explanation
Global Mode
snmp-server enable
Enable snmp server function in
commander switch and member
switch.
Note: Ensure the SNMP server
function is enabled in member switch
when commander switch visiting
member switch by sn. The
commander switch visit member
switch via configure character string
<commander-community>@sw<me
mber id>.
6-5
6.3 Examples of Cluster Administration
Scenario:
Among the four switches -- SW1, SW2, SW3 and SW4 -- SW1 is the command switch and the
other switches are member switch. The SW2 and SW4 are directly connected with the
command switch while SW3 connects to the command switch through SW2.
E1 E2 E1 E2 E1 E1
SW1 SW2 SW3 SW4
Figure 6-1: Examples of Cluster
Configuration Procedure
1. Configure the command switch
Configuration of SW1:
Switch(config)#cluster run
Switch(config)#cluster ip-pool 10.2.3.4
Switch(config)#cluster commander 5526
Switch(config)#cluster auto-add
2. Configure the member switch
Configuration of SW2-SW4
Switch(config)#cluster run
6.4 Cluster Administration Troubleshooting
When encountering problems in applying the cluster admin, please check the following
possible causes:
The command switch should be correctly configured and the automatically added
function (cluster auto-add) is enabled. The ports are connected to the command switch
and member switch belongs to the cluster vlan.
After cluster commander is enabled in VLAN1 of the command switch, please don’t
enable a routing protocol (RIP, OSPF, BGP) in this VLAN in order to prevent the routing
6-6
protocol from broadcasting the private cluster addresses in this VLAN to other switches
and cause routing loops.
Whether the connection between the command switch and the member switch is correct.
We can use the debug cluster packets to check if the command and the member
switches can receive and process related cluster admin packets correctly.
6-7
Chapter 7 Port Configuration
7.1 Introduction to Port
Switch contains Cable ports and Combo ports. The Combo ports can be configured as either
1000GX-TX ports or SFP Gigabit fiber ports. If the user needs to configure some network ports,
he/she can use the interface Ethernet <interface-list> command to enter the appropriate
Ethernet port configuration mode, where <interface-list> stands for one or more ports. If
<interface-list> contains multiple ports, special characters such as ';' or '-' can be used to
separate ports, ';' is used for discrete port numbers and '-' is used for consecutive port
numbers. Suppose an operation should be performed on ports 2,3,4,5 the command would
look like: interface Ethernet 1/2-5. Port speed, duplex mode and traffic control can be
configured under Ethernet Port Mode causing the performance of the corresponding network
ports to change accordingly.
7.2 Network Port Configuration Task List
1. Enter the network port configuration mode
2. Configure the properties for the network ports
(1) Configure combo mode for combo ports
(2) Enable/Disable ports
(3) Configure port names
(4) Configure port cable types
(5) Configure port speed and duplex mode
(6) Configure bandwidth control
(7) Configure traffic control
(8) Enable/Disable port loopback function
(9) Configure broadcast storm control function for the switch
(10) Configure scan port mode
(11) Configure rate-violation control of the port
(12) Configure interval of port-rate-statistics
3. Virtual cable test
7-8
1. Enter the Ethernet port configuration mode
Command Explanation
Global Mode
interface ethernet <interface-list> Enters the network port configuration mode.
2. Configure the properties for the Ethernet ports
Command Explanation
Port mode
media-type {copper |
copper-preferred-auto | fiber |
sfp-preferred-auto}
Sets the combo port mode (combo ports
only).
shutdown
no shutdown Enables/Disables specified ports.
description <string>
no description
Specifies or cancels the name of specified
ports.
mdi {auto | across | normal}
no mdi
Sets the cable type for the specified port; this
command is not supported by combo port
and fiber port of switch.
speed-duplex {auto [10 [100 [1000]]
[auto | full | half |]] | force10-half |
force10-full | force100-half |
force100-full | force100-fx
[module-type {auto-detected |
no-phy-integrated | phy-integrated}] |
{{force1g-half | force1g-full}
[nonegotiate [master | slave]]}|
force10g-full}
no speed-duplex
Sets port speed and duplex mode of
100/1000BASE-TX or 1000BASE-X ports.
The no format of this command restores the
default setting, i.e., negotiates speed and
duplex mode automatically.
negotiation {on|off} Enables/Disables the auto-negotiation
function of 1000BASE-X ports.
bandwidth control <bandwidth> [both |
receive | transmit]
no bandwidth control
Sets or cancels the bandwidth used for
incoming/outgoing traffic for specified ports.
flow control
no flow control
Enables/Disables traffic control function for
specified ports.
7-9
loopback
no loopback
Enables/Disables loopback test function for
specified ports.
storm control {unicast | broadcast |
multicast} {kbps <Kbits> | pps <PPS>}
no strom control {unicast | broadcast |
multicast}>
Enables the storm control function for
broadcasts, multicasts and unicasts with
unknown destinations (short for broadcast),
and sets the allowed broadcast packet
number or the bit number passing per
second; the no format of this command
disables the broadcast storm control
function.
switchport flood-control
{ bcast|mcast|ucast }
no switchport flood-control
{ bcast|mcast|ucast }
Configure that switch does not transmit
broadcast, unknown multicast or unknown
unicast packets any more to the specified
port; no command restores the default
configuration. Note: This switch does not
support this command.
port-scan-mode {interrupt | poll}
no port-scan-mode
Configure port-scan-mode as interrupt or poll
mode, the no command restores the default
port-scan-mode.
rate-violation <200-2000000> [recovery
<0-86400>]
no rate-violation
Set the max. packet reception rate of a port.
If the rate of the received packet violates the
packet reception rate, shut down this port
and configure the recovery time, the default
is 300s. The no command will disable the
rate-violation function of a port.
Command Explanation
Port Mode
switchport discard packet { all |
untag }
no switchport discard packet { all |
untag }
Configure the port not to receive any packet
or untag; the no command cancel the
restriction of discard, it means the port is
allowed to receive any packet or untag.
Command Explanation
Global Mode
port-rate-statistics interval <interval
-value>
Configure the interval of port-rate-statistics.
7-10
3. Virtual cable test
Command Explanation
Admin Mode
virtual-cable-test interface ethernet
<interface-list>
Test virtual cables of the port.
7.3 Port Configuration Example
1/7 Switch 1
1/9
1/10
1/12 Switch 21/8
Switch 3
Figure 7-1: Port Configuration Example
No VLAN has been configured in the switches; default VLAN1 is used.
Switch Port Property
Switch1 1/7 Ingress bandwidth limit: 50 M
Switch2 1/8 Mirror source port
1/9 100Mbps full, mirror source port
1/10 1000Mbps full, mirror destination port
Switch3 1/12 100Mbps full
The configurations are listed below:
Switch 1:
Switch1(config)#interface ethernet 1/7
Switch1(Config-If-Ethernet1/7)#bandwidth control 50000 receive
7-11
Switch 2:
Switch2(config)#interface ethernet 1/9
Switch2(Config-If-Ethernet1/9)#speed-duplex force100-full
Switch2(Config-If-Ethernet1/9)#exit
Switch2(config)#interface ethernet 1/10
Switch2(Config-If-Ethernet1/10)#speed-duplex force1g-full
Switch2(Config-If-Ethernet1/10)#exit
Switch2(config)#monitor session 1 source interface ethernet 1/8;1/9
Switch2(config)#monitor session 1 destination interface ethernet 1/10
Switch 3:
Switch3(config)#interface ethernet 1/12
Switch3(Config-If-Ethernet1/12)#speed-duplex force100-full
Switch3(Config-If-Ethernet1/12)#exit
7.4 Port Troubleshooting
Here are some situations that frequently occurs in port configuration and the following
solutions are advised:
Two connected fiber interfaces won’t link up if one interface is set to auto-negotiation but
the other to forced speed/duplex. This is determined by IEEE 802.3.
The following combinations are not recommended: enabling traffic control as well as
setting multicast limiting for the same port; setting broadcast, multicast and unknown
destination unicast control as well as port bandwidth limiting for the same port. If such
combinations are set, the port throughput may fall below the expected performance.
7-12
Chapter 8 Port Isolation Function
Configuration
8.1 Introduction to Port Isolation Function
Port isolation is an independent port-based function working in an inter-port way, which
isolates flows of different ports from each other. With the help of port isolation, users can
isolate ports within a VLAN to save VLAN resources and enhance network security. After this
function is configured, the ports in a port isolation group will be isolated from each other, while
ports belonging to different isolation groups or no such group can forward data to one another
normally. No more than 16 port isolation groups can a switch has.
8.2 Task Sequence of Port Isolation
1. Create an isolate port group
2. Add Ethernet ports into the group
3. Display the configuration of port isolation
1. Create an isolate port group
Command Explanation
Global Mode
isolate-port group <WORD>
no isolate-port group <WORD>
Set a port isolation group; the no operation of
this command will delete the port isolation
group.
2. Add Ethernet ports into the group
Command Explanation
Global Mode
isolate-port group <WORD> switchport
interface [ethernet] <IFNAME>
no isolate-port group <WORD>
switchport interface [ethernet] <IFNAME>
Add one port or a group of ports into a port
isolation group to isolate, which will become
isolated from the other ports in the group; the
no operation of this command will remove one
port or a group of ports out of a port isolation
group.
8-13
3. Display the configuration of port isolation
Command Explanation
Admin and Global Mode
show isolate-port group [ <WORD> ]
Display the configuration of port isolation,
including all configured port isolation groups
and Ethernet ports in each group.
8.3 Port Isolation Function Typical Examples
Figure 8-1: Typical example of port isolation function
The topology and configuration of switches are showed in the figure above, with e1/1, e1/10
and e1/15 all belonging to VLAN 100. The requirement is that, after port isolation is enabled on
switch S1, e1/1 and e1/10 on switch S1 cannot communicate with each other, while both of
them can communicate with the uplink port e1/15. That is, the communication between any
pair of downlink ports is disabled while that between any downlink port and a specified uplink
port is normal. The uplink port can communicate with any port normally.
The configuration of S1:
Switch(config)#isolate-port group test
Switch(config)#isolate-port group test switchport interface ethernet 1/1;1/10
e1/1
e1/15
Vlan
S1 e1/10
S3S2
8-14
Chapter 9 Port Loopback Detection
Function Configuration
9.1 Introduction to Port Loopback Detection Function
With the development of switches, more and more users begin to access the network through
Ethernet switches. In enterprise network, users access the network through Layer 2 switches,
which means urgent demands for both internet and the internal Layer 2 interwork. When Layer
2 interwork is required, the messages will be forwarded through MAC addressing the accuracy
of which key is the correct one interworking between users. In Layer 2 switching, the
messages are forwarded through MAC addressing. Layer 2 devices learn MAC addresses via
learned MAC address, that is, when the port receives a message from an unknown source --
MAC address, it will add this MAC to the receive port, so that the following messages with a
destination of this MAC can be forwarded directly, which also means learned MAC address
once and for all can forward messages.
When a new source MAC is already learnt by the Layer 2 device, only with a different source
port, the original source port will be modified to the new one, which means to correspond the
original MAC address with the new port. As a result, if there is any loopback existing in the link,
all MAC addresses within the whole Layer 2 network will be corresponded with the port where
the loopback appears (usually the MAC address will be frequently shifted from one port to
another), causing the Layer 2 network to collapse. That is why it is a necessity to check port
loopbacks in the network. When a loopback is detected, the detected device should send
alarms to the network management system, ensuring the network manager is able to discover,
locate and solve the problem in the network and protect users from a long-lasting
disconnected network.
Since detecting loopbacks can make dynamic judgment of the existence of loopbacks in the
link and tell whether it has gone, the devices supporting port control (such as port isolation and
port MAC address learning control) can maintain that automatically, which will not only reduce
the burden of network managers but also response time, minimizing the effect causing
loopbacks to the network.
9-15
9.2 Port Loopback Detection Function Configuration
Task List
1． Configure the time interval of loopback detection
2． Enable the function of port loopback detection
3． Configure the control method of port loopback detection
4． Display and debug the relevant information of port loopback detection
5． Configure the loopback-detection control mode (automatic recovery enabled or not)
1．Configure the time interval of loopback detection
Command Explanation
Global Mode
loopback-detection interval-time
<loopback> <no-loopback>
no loopback-detection interval-time
Configure the time interval of loopback
detection.
2．Enable the function of port loopback detection
Command Explanation
Port Mode
loopback-detection specified-vlan
<vlan-list>
no loopback-detection specified-vlan
<vlan-list>
Enable and disable the function of port
loopback detection.
3．Configure the control method of port loopback detection
Command Explanation
Port Mode
loopback-detection control {shutdown
|block| learning}
no loopback-detection control
Enable and disable the function of port
loopback detection control.
9-16
4．Display and debug the relevant information of port loopback detection
Command Explanation
Admin Mode
debug loopback-detection
no debug loopback-detection
Enable the debug information of the
function module of port loopback detection.
The no operation of this command will
disable the debug information.
show loopback-detection [interface
<interface-list>]
Display the state and result of the loopback
detection of all ports, if no parameter is
provided; otherwise, display the state and
result of the corresponding ports.
5. Configure the loopback-detection control mode (automatic recovery enabled or not)
Command Explanation
Global Mode
loopback-detection control-recovery
timeout <0-3600>
Configure the loopback-detection control
mode (automatic recovery enabled or not)
or recovery time.
9.3 Port Loopback Detection Function Example
Network Topology
SWITCH
Figure 9-1: Typical example of port loopback detection
9-17
As shown in the above configuration, the switch will detect the existence of loopbacks in the
network topology. After enabling the function of loopback detection on the port connecting the
switch with the outside network, the switch will notify the connected network about the
existence of a loopback, and control the port on the switch to guarantee the normal operation
of the whole network.
The configuration task sequence of SWITCH:
Switch(config)#loopback-detection interval-time 35 15
Switch(config)#interface ethernet 1/1
Switch(Config-If-Ethernet1/1)#loopback-detection special-vlan 1-3
Switch(Config-If-Ethernet1/1)#loopback-detection control block
If adopting the control method of block, MSTP should be globally enabled. And the
corresponding relation between the spanning tree instance and the VLAN should be
configured.
Switch(config)#spanning-tree
Switch(config)#spanning-tree mst configuration
Switch(Config-Mstp-Region)#instance 1 vlan 1
Switch(Config-Mstp-Region)#instance 2 vlan 2
Switch(Config-Mstp-Region)#
9.4 Port Loopback Detection Troubleshooting
The function of port loopback detection is disabled by default and should only be enabled if
required.
9-18
Chapter 10 ULDP Function
Configuration
10.1 Introduction to ULDP Function
Unidirectional link is a common error state of link in networks, especially in fiber links.
Unidirectional link means that only one port of the link can receive messages from the other
port, while the latter one can not receive messages from the former one. Since the physical
layer of the link is connected and works normal, via the checking mechanism of the physical
layer, communication problems between the devices can not be found. As shown in Graph, the
problem in fiber connection can not be found through mechanisms in physical layer like
automatic negotiation.
Figure 10-1: Fiber Cross Connection
Figure 10-2: One End of Each Fiber Not Connected
Switch A
g1/1
g1/2 g1/3
g1/4
Switch B
Switch A
Switch B g1/2
g1/1
Switch Cg1/3
10-19
This kind of problem often appears in the following situations: GBIC (Giga Bitrate Interface
Converter) or interfaces have problems, software problems, hardware becomes unavailable or
operates abnormally. Unidirectional link will cause a series of problems, such as spinning tree
topological loop, broadcast black hole.
ULDP (Unidirectional Link Detection Protocol) can help avoid disasters that could happen in
the situations mentioned above. In a switch connected via fibers or copper Ethernet line (like
ultra five-kind twisted pair), ULDP can monitor the link state of physical links. Whenever a
unidirectional link is discovered, it will send warnings to users and can disable the port
automatically or manually according to users’ configuration.
The ULDP of switches recognizes remote devices and check the correctness of link
connections via interacting ULDP messages. When ULDP is enabled on a port, protocol state
machine will be started, which means different types of messages will be sent at different
states of the state machine to check the connection state of the link by exchanging information
with remote devices. ULDP can dynamically study the interval at which the remote device
sends notification messages and adjust the local TTL (time to live) according to that interval.
Besides, ULDP provides the reset mechanism, when the port is disabled by ULDP, it can
check again through reset mechanism. The time intervals of notification messages and reset in
ULDP can be configured by users, so that ULDP can respond faster to connection errors in
different network environments.
The premise of ULDP working normally is that link works in duplex mode, which means ULDP
is enabled on both ends of the link, using the same method of authentication and password.
10.2 ULDP Configuration Task Sequence
1. Enable ULDP function globally
2. Enable ULDP function on a port
3. Configure aggressive mode globally
4. Configure aggressive mode on a port
5. Configure the method to shut down unidirectional link
6. Configure the interval of Hello messages
7. Configure the interval of Recovery
8. Reset the port shut down by ULDP
9. Display and debug the relative information of ULDP
10-20
1. Enable ULDP function globally
Command Explanation
Global Mode
uldp enable
uldp disable Globally enable or disable ULDP function.
2. Enable ULDP function on a port
Command Explanation
Port Mode
uldp enable
uldp disable Enable or disable ULDP function on a port.
3. Configure aggressive mode globally
Command Explanation
Global Mode
uldp aggressive-mode
no uldp aggressive-mode Set the global working mode.
4. Configure aggressive mode on a port
Command Explanation
Port Mode
uldp aggressive-mode
no uldp aggressive-mode Set the working mode of the port.
5. Configure the method to shut down unidirectional link
Command Explanation
Global Mode
uldp manual-shutdown
no uldp manual-shutdown
Configure the method to shut down
unidirectional link.
6. Configure the interval of Hello messages
Command Explanation
10-21
Global Mode
uldp hello-interval <integer>
no uldp hello-interval
Configure the interval of Hello messages,
ranging from 5 to 100 seconds. The value
is 10 seconds by default.
7. Configure the interval of Recovery
Command Explanation
Global Mode
uldp recovery-time <integer>
no uldp recovery-time <integer>
Configure the interval of Recovery reset,
ranging from 30 to 86400 seconds. The
value is 0 second by default.
8. Reset the port shut down by ULDP
Command Explanation
Global or Port Mode
uldp reset
Reset all ports in global configuration
mode;
Reset the specified port in
port configuration mode.
9. Display and debug the related information of ULDP
Command Explanation
Admin Mode
show uldp [interface ethernet IFNAME]
Display ULDP information. No parameter
means to display global ULDP information.
The parameter specifying a port will display
global information and the neighbor
information of the port.
debug uldp fsm interface ethernet
<IFname>
no debug uldp fsm interface ethernet
<IFname>
Enable or disable the debug switch of the
state machine transition information on the
specified port.
debug uldp error
no debug uldp error
Enable or disable the debug switch of error
information.
debug uldp event
no debug uldp event
Enable or disable the debug switch of
event information.
10-22
debug uldp packet {receive|send}
no debug uldp packet {receive|send}
Enable or disable the type of messages
can be received and sent on all ports.
debug uldp {hello|probe|echo| unidir|all}
[receive|send] interface ethernet
<IFname>
no debug uldp {hello|probe|echo|
unidir|all} [receive|send] interface
ethernet <IFname>
Enable or disable the content detail of a
particular type of messages can be
received and sent on the specified port.
10.3 ULDP Function Typical Examples
Switch A
g1/2
Switch B
g1/4
g1/3
g1/1
PC2
PC1
Figure 10-3 Fiber Cross Connection
In the network topology in Graph, port g1/1 and port g1/2 of SWITCH A as well as port g1/3
and port g1/4 of SWITCH B are all fiber ports. And the connection is cross connection. The
physical layer is connected and works normally, but the data link layer is abnormal. ULDP can
discover and disable this kind of error state of link. The final result is that port g1/1, g1/2 of
SWITCH A and port g1/3, g1/4 of SWITCH B are all shut down by ULDP. Only when the
connection is correct, can the ports work normally (won’t be shut down).
Switch A configuration sequence:
SwitchA(config)#uldp enable
SwitchA(config)#interface ethernet 1/1
SwitchA(Config-If-Ethernet1/1)#uldp enable
SwitchA(Config-If-Ethernet1/1)#exit
SwitchA(config)#interface ethernet 1/2
10-23
SwitchA(Config-If-Ethernet1/2)#uldp enable
Switch B configuration sequence:
SwitchB(config)#uldp enable
SwitchB(config)#interface ethernet1/3
SwitchB(Config-If-Ethernet1/3)#uldp enable
SwitchB(Config-If-Ethernet1/3)#exit
SwitchB(config)#interface ethernet 1/4
SwitchB(Config-If-Ethernet1/4)#uldp enable
As a result, port g1/1, g1/2 of SWITCH A are all shut down by ULDP, and there is notification
information on the CRT terminal of PC1.
%Oct 29 11:09:50 2007 A unidirectional link is detected! Port Ethernet1/1 need to be shut
down!
%Oct 29 11:09:50 2007 Unidirectional port Ethernet1/1 is shut down!
%Oct 29 11:09:50 2007 A unidirectional link is detected! Port Ethernet1/2 need to be shut
down!
%Oct 29 11:09:50 2007 Unidirectional port Ethernet1/2 is shut down!
Port g1/3, and port g1/4 of SWITCH B are all shut down by ULDP, and there is notification
information on the CRT terminal of PC2.
%Oct 29 11:09:50 2007 A unidirectional link is detected! Port Ethernet1/3 need to be shut
down!
%Oct 29 11:09:50 2007 Unidirectional port Ethernet1/3 is shut down!
%Oct 29 11:09:50 2007 A unidirectional link is detected! Port Ethernet1/4 need to be shut
down!
%Oct 29 11:09:50 2007 Unidirectional port Ethernet1/4 is shut down!
10.4 ULDP Troubleshooting
Configuration Notice:
In order to ensure that ULDP can discover that the one of fiber ports has not connected
or the ports are incorrectly cross connected, the ports have to work in duplex mode and
have the same rate.
If the automatic negotiation mechanism of the fiber ports with one port misconnected
decides the working mode and rate of the ports, ULDP won’t take effect whether it is
enabled or not. In such situation, the port is considered as “Down”.
10-24
In order to make sure that neighbors can be correctly created and unidirectional links can
be correctly discovered, it is required that both end of the link should enable ULDP, using
the same authentication method and password. At present, no password is needed on
both ends.
The hello interval of sending hello messages can be changed (it is10 seconds by default
and ranges from 5 to 100 seconds) so that ULDP can respond faster to connection errors
of links in different network environments. But this interval should be less than 1/3 of the
STP convergence time. If the interval is too long, a STP loop will be generated before
ULDP discovers and shuts down the unidirectional connection port. If the interval is too
short, the network burden on the port will be increased, which means a reduced
bandwidth.
ULDP does not handle any LACP event. It treats every link of TRUNK group (like
Port-channel, TRUNK ports) as independent, and handles each of them respectively.
ULDP does not compact with similar protocols of other vendors, which means users can
not use ULDP on one end and use other similar protocols on the other end.
ULDP function is disabled by default. After globally enabling ULDP function, the debug
switch can be enabled simultaneously to check the debug information. There are several
DEBUG commands provided to print debug information, such as information of events,
state machine, errors and messages. Different types of message information can also be
printed according to different parameters.
The Recovery timer is disabled by default and will only be enabled when the users have
configured recovery time (30-86400 seconds).
Reset command and reset mechanism can only reset the ports automatically shut down
by ULDP. The ports shut down manually by users or by other modules won’t be reset by
ULDP.
10-25
Chapter 11 LLDP Function Operation
Configuration
11.1 Introduction to LLDP Function
Link Layer Discovery Protocol (LLDP) is a new protocol defined in 802.1ab. It enables
neighbor devices to send notices of their own state to other devices, and enables all ports of
every device to store information about them. If necessary, the ports can also send update
information to the neighbor devices directly connected to them, and those neighbor devices
will store the information in standard SNMP MIBs. The network management system can
check the layer-two connection state from MIB. LLDP won’t configure or control network
elements or flows, but only report the configuration of layer-two. Another content of 802.1ab is
to utilizing the information provided by LLDP to find the conflicts in layer-two. IEEE now uses
the existing physical topology, interfaces and Entity MIBs of IETF.
To simplify, LLDP is a neighbor discovery protocol. It defines a standard method for Ethernet
devices, such as switches, routers and WLAN access points, to enable them to notify their
existence to other nodes in the network and store the discovery information of all neighbor
devices. For example, the detail information of the device configuration and discovery can both
use this protocol to advertise.
In specific, LLDP defines a general advertisement information set, a transportation
advertisement protocol and a method to store the received advertisement information. The
device to advertise its own information can put multiple pieces of advertisement information in
one LAN data packet to transport. The type of transportation is the type length value (TLV) field.
All devices supporting LLDP have to support device ID and port ID advertisement, but it is
assumed that, most devices should also support system name, system description and system
performance advertisement. System name and system description advertisement can also
provide useful information for collecting network flow data. System description advertisement
can include data such as the full name of the advertising device, hardware type of system, the
version information of software operation system and so on.
802.1AB Link Layer Discovery Protocol will make searching the problems in an enterprise
network an easier process and can strengthen the ability of network management tools to
discover and maintain accurate network topology structure.
11-26
Many kinds of network management software use “Automated Discovery” function to trace the
change and condition of topology, but most of them can reach layer-three and classify the
devices into all IP subnets at best. This kind of data are very primitive, only referring to basic
events like the adding and removing of relative devices instead of details about where and how
these devices operate with the network.
Layer 2 discovery covers information like which devices have which ports, which switches
connect to other devices and so on, it can also display the routs between clients, switches,
routers, application servers and network servers. Such details will be very meaningful for
schedule and investigate the source of network failure.
LLDP will be a very useful management tool, providing accurate information about network
mirroring, flow data and searching network problems.
11.2 LLDP Function Configuration Task Sequence
1. Globally enable LLDP function
2. Configure the port-based LLDP function switch
3. Configure the operating state of port LLDP
4. Configure the intervals of LLDP updating messages
5. Configure the aging time multiplier of LLDP messages
6. Configure the sending delay of updating messages
7. Configure the intervals of sending Trap messages
8. Configure to enable the Trap function of the port
9. Configure the optional information-sending attribute of the port
10. Configure the size of space to store Remote Table of the port
11. Configure the type of operation when the Remote Table of the port is full
12. Display and debug the relative information of LLDP
1. Globally enable LLDP function
Command Explanation
Global Mode
lldp enable
lldp disable Globally enable or disable LLDP function.
11-27
2. Configure the port-based LLDP function switch
Command Explanation
Port Mode
lldp enable
lldp disable
Configure the port-based LLDP function
switch.
3. Configure the operating state of port LLDP
Command Explanation
Port Mode
lldp mode (send|receive|both|disable) Configure the operating state of port
LLDP.
4. Configure the intervals of LLDP updating messages
Command Explanation
Global Mode
lldp tx-interval <integer>
no lldp tx-interval
Configure the intervals of LLDP updating
messages as the specified value or
default value.
5. Configure the aging time multiplier of LLDP messages
Command Explanation
Global Mode
lldp msgTxHold <value>
no lldp msgTxHold
Configure the aging time multiplier of
LLDP messages as the specified value or
default value.
6. Configure the sending delay of updating messages
Command Explanation
Global Mode
lldp transmit delay <seconds>
no lldp transmit delay
Configure the sending delay of updating
messages as the specified value or
default value.
11-28
7. Configure the intervals of sending Trap messages
Command Explanation
Global Mode
lldp notification interval <seconds>
no lldp notification interval
Configure the intervals of sending
Trap messages as the specified value or
default value.
8. Configure to enable the Trap function of the port
Command Explanation
Port Mode
lldp trap <enable|disable> Enable or disable the Trap function of
the port.
9. Configure the optional information-sending attribute of the port
Command Explanation
Port Mode
lldp transmit optional tlv [portDesc]
[sysName] [sysDesc] [sysCap]
no lldp transmit optional tlv
Configure the optional
information-sending attribute of the port
as the option value of default values.
10. Configure the size of space to store Remote Table of the port
Command Explanation
Port Mode
lldp neighbors max-num < value >
no lldp neighbors max-num
Configure the size of space to store
Remote Table of the port as the
specified value or default value.
11. Configure the type of operation when the Remote Table of the port is full
Command Explanation
Port Mode
lldp tooManyNeighbors {discard |
delete}
Configure the type of operation when the
Remote Table of the port is full.
11-29
12. Display and debug the relative information of LLDP
Command Explanation
Admin and Global Mode
show lldp Display the current LLDP configuration
information.
show lldp interface ethernet <IFNAME> Display the LLDP configuration
information of the current port.
show lldp traffic Display the information of all kinds of
counters.
show lldp neighbors interface
ethernet < IFNAME >
Display the information of LLDP
neighbors of the current port.
show debugging lldp Display all ports with LLDP debug
enabled.
Admin Mode
debug lldp
no debug lldp Enable or disable the DEBUG switch.
debug lldp packets interface ethernet
<IFNAME>
no debug lldp packets interface ethernet
<IFNAME>
Enable or disable the DEBUG
packet-receiving and sending function in
port or global mode.
Port Mode
clear lldp remote-table Clear Remote-table of the port.
11.3 LLDP Function Typical Example
Figure 11-1: LLDP Function Typical Configuration Example
11-30
In the network topology graph above, the port 1,3 of SWITCH B are connected to port 2,4 of
SWITCH A. Port 1 of SWITCH B is configured to message-receiving-only mode, Option TLV of
port 4 of SWITCH A is configured as portDes and SysCap.
SWITCH A configuration task sequence:
SwitchA(config)# lldp enable
SwitchA(config)#interface ethernet 1/4
SwitchA(Config-If-Ethernet1/4)#lldp transmit optional tlv portDesc sysCap
SwitchA(Config-If-Ethernet1/4)exit
SWITCH B configuration task sequence:
SwitchB(config)#lldp enable
SwitchB(config)#interface ethernet1/1
SwitchB(Config-If-Ethernet1/1)#lldp mode receive
SwitchB(Config-If-Ethernet1/1)#exit
11.4 LLDP Function Troubleshooting
LLDP function is disabled by default. After enabling the global switch of LLDP, users can
enable the debug switch “debug lldp” simultaneously to check debug information.
Using “show” function of LLDP function can display the configuration information in global
or port configuration mode.
11-31
Chapter 12 Port Channel Configuration
12.1 Introduction to Port Channel
To understand Port Channel, Port Group should be introduced first. Port Group is a group of
physical ports in the configuration level; only physical ports in the Port Group can take part in
link aggregation and become a member port of a Port Channel. Logically, Port Group is not a
port but a port sequence. Under certain conditions, physical ports in a Port Group perform port
aggregation to form a Port Channel that has all the properties of a logical port, therefore it
becomes an independent logical port. Port aggregation is a process of logical abstraction to
abstract a set of ports (port sequence) with the same properties to a logical port. Port Channel
is a collection of physical ports and used logically as one physical port. Port Channel can be
used as a normal port by the user, and can not only add network’s bandwidth, but also provide
link backup. Port aggregation is usually used when the switch is connected to routers, PCs or
other switches.
Figure 12-1: Port aggregation
As shown in the above, S1 is aggregated to a Port Channel, the bandwidth of this Port
Channel is the total of all the four ports. If traffic from S1 needs to be transferred to S2 through
the Port Channel, traffic allocation calculation will be performed based on the source MAC
address and the lowest bit of target MAC address. The calculation result will decide which port
to convey the traffic. If a port in Port Channel fails, the other ports will undertake traffic of that
port through a traffic allocation algorithm. This algorithm is carried out by the hardware.
Switch offers two methods for configuring port aggregation: manual Port Channel creation and
LACP (Link Aggregation Control Protocol) dynamic Port Channel creation. Port aggregation
can only be performed on ports in full-duplex mode.
S1
S2
12-32
For Port Channel to work properly, member ports of the Port Channel must have the same
properties as follows:
All ports are in full-duplex mode.
All Ports are of the same speed.
All ports are Access ports and belong to the same VLAN or are all TRUNK ports, or are
all Hybrid ports.
If the ports are all TRUNK ports or Hybrid ports, then their “Allowed VLAN” and “Native
VLAN” property should also be the same.
If Port Channel is configured manually or dynamically on switch, the system will automatically
set the port with the smallest number to be Master Port of the Port Channel. If the spanning
tree function is enabled in the switch, the spanning tree protocol will regard Port Channel as a
logical port and send BPDU frames via the master port.
Port aggregation is closely related with switch hardware. Switch allow physical port
aggregation of any two switches, maximum 14 groups and 8 ports in each port group are
supported.
Once ports are aggregated, they can be used as a normal port. Switch have a built-in
aggregation interface configuration mode, the user can perform related configuration in this
mode just like in the VLAN and physical interface configuration mode.
12.2 Brief Introduction to LACP
LACP (Link Aggregation Control Protocol) is a kind of protocol based on IEEE802.3ad
standard to implement the link dynamic aggregation. LACP protocol uses LACPDU (Link
Aggregation Control Protocol Data Unit) to exchange the information with the other end. After
LACP protocol of the port is enabled, this port will send LACPDU to the other end to notify the
system priority, the MAC address of the system, the priority of the port, the port ID and the
operation Key. After the other end receives the information, the information is compared with
the saving information of other ports to select the port which can be aggregated, accordingly,
both sides can reach an agreement about the ports join or exit the dynamic aggregation group.
The operation Key is created by LACP protocol according to the combination of
configuration (speed, duplex, basic configuration, management Key) of the ports to be
aggregated.
12-33
After the dynamic aggregation port enables LACP protocol, the management Key is 0 by
default. After the static aggregation port enables LACP, the management Key of the port is the
same with the ID of the aggregation group.
For the dynamic aggregation group, the members of the same group have the same operation
Key, for the static aggregation group, the ports of Active have the same operation Key.
The port aggregation is that multi-ports are aggregated to form an aggregation group, so as to
implement the out/in load balance in each member port of the aggregation group and provides
the better reliability.
12.2.1 Static LACP Aggregation
Static LACP aggregation is enforced by users configuration, and do not enable LACP protocol.
When configuring static LACP aggregation, use “on” mode to force the port to enter the
aggregation group.
12.2.2 Dynamic LACP Aggregation
1. The summary of the dynamic LACP aggregation
Dynamic LACP aggregation is an aggregation created/deleted by the system automatically; it
does not allow the user to add or delete the member ports of the dynamic LACP aggregation.
The ports, which have the same attribute of speed and duplex, are connected to the same
device, have the same basic configuration, and can be dynamically aggregated together. Only
one port can create the dynamic aggregation and that is the single port aggregation. In the
dynamic aggregation, LACP protocol of the port is in the enable state.
2. The port state of the dynamic aggregation group
In dynamic aggregation group, the ports have two states: selected or standby. Both selected
ports and standby ports can receive and send LACP protocol, but standby ports cannot
forward the data packets.
The limitation of the max. port number is in the aggregation group. If the current number of the
member ports exceeds the limitation of the max. port number, then the system of this end will
negotiate with the other end to decide the port state according to the port ID. The negotiation
steps are as follows:
Compare ID of the devices (the priority of the system + the MAC address of the system). First,
compare the priority of the systems, if they are the same, then compare the MAC address of
the systems. The end with a small device ID has the high priority.
12-34
Compare the ID of the ports (the priority of the port + the ID of the port). For each port in the
side of the device which has the high device priority, first, compare the priority of the ports, if
the priorities are same, then compare the ID of the ports. The port with a small port ID is
selected, and the others become the standby ports.
In an aggregation group, the port which has the smallest port ID and is in the selected state will
be the master port while the other ports in the selected state will be the member port.
12.2.3 Port Channel Configuration Task List
1. Create a port group in Global Mode
2. Add ports to the specified group from the Port Mode of respective ports
3. Enter port-channel configuration mode
4. Set load-balance method for port-group
5. Set the system priority of LACP protocol
6. Set the port priority of the current port in LACP protocol
7. Set the timeout mode of the current port in LACP protocol
1. Creating a port group
Command Explanation
Global Mode
port-group <port-group-number>
no port-group <port-group-number> Create or delete a port group.
2. Add physical ports to the port group
Command Explanation
Port Mode
port-group <port-group-number> mode
{active | passive | on}
no port-group
Add the ports to the port group and set their
mode.
12-35
3. Enter port-channel configuration mode.
Command Explanation
Global Mode
interface port-channel
<port-channel-number> Enter port-channel configuration mode.
4. Set load-balance method for port-group
Command Explanation
Aggregation Port Mode
load-balance {src-mac | dst-mac | dst-src-mac |
src-ip | dst-ip | dst-src-ip} Set load-balance for port-group.
5. Set the system priority of LACP protocol
Command Explanation
Global Mode
lacp system-priority <system-priority>
no lacp system-priority
Set the system priority of LACP
protocol, the no command restores
the default value.
6. Set the port priority of the current port in LACP protocol
Command Explanation
Port Mode
lacp port-priority <port-priority>
no lacp port-priority
Set the port priority in LACP protocol.
The no command restores the default
value.
7. Set the timeout mode of the current port in LACP protocol
Command Explanation
Port Mode
lacp timeout {short | long}
no lacp timeout
Set the timeout mode in LACP
protocol. The no command restores
the default value.
12-36
12.3 Port Channel Examples
Scenario 1: Configuring Port Channel in LACP.
S1
S2
Figure 12-2: Configure Port Channel in LACP
The switches in the description below are all switches and as shown in the figure, ports 1, 2, 3,
4 of S1 are access ports and add them to group1 with active mode. Ports 6, 8, 9, 10 of S2 are
access ports and add them to group2 with passive mode. All the ports should be connected
with cables.
The configuration steps are listed below:
Switch1#config
Switch1(config)#interface ethernet 1/1-4
Switch1(Config-If-Port-Range)#port-group 1 mode active
Switch1(Config-If-Port-Range)#exit
Switch1(config)#interface port-channel 1
Switch1(Config-If-Port-Channel1)#
Switch2#config
Switch2(config)#port-group 2
Switch2(config)#interface ethernet 1/6
Switch2(Config-If-Ethernet1/6)#port-group 2 mode passive
Switch2(Config-If-Ethernet1/6)#exit
Switch2(config)#interface ethernet 1/8-10
Switch2(Config-If-Port-Range)#port-group 2 mode passive
Switch2(Config-If-Port-Range)#exit
Switch2(config)#interface port-channel 2
12-37
Switch2(Config-If-Port-Channel2)#
Configuration result:
Shell prompts ports aggregated successfully after a while, now ports 1, 2, 3, 4 of S1 form an
aggregated port named “Port-Channel1”, ports 6, 8, 9, 10 of S2 form an aggregated port
named “Port-Channel2”; can be configured in their respective aggregated port modes.
Scenario 2: Configuring Port Channel in ON mode.
S1
S2
Figure 12-3: Configure Port Channel in ON mode
As shown in the figure, ports 1, 2, 3, 4 of S1 are access ports and add them to group1 with “on”
mode. Ports 6, 8, 9, 10 of S2 are access ports and add them to group2 with “on” mode.
The configuration steps are listed below:
Switch1#config
Switch1(config)#interface ethernet 1/1
Switch1(Config-If-Ethernet1/1)#port-group 1 mode on
Switch1(Config-If-Ethernet1/1)#exit
Switch1(config)#interface ethernet 1/2
Switch1 (Config-If-Ethernet1/2)#port-group 1 mode on
Switch1 (Config-If-Ethernet1/2)#exit
Switch1 (config)#interface ethernet 1/3
Switch1 (Config-If-Ethernet1/3)#port-group 1 mode on
Switch1 (Config-If-Ethernet1/3)#exit
Switch1 (config)#interface ethernet 1/4
Switch1 (Config-If-Ethernet1/4)#port-group 1 mode on
Switch1 (Config-If-Ethernet1/4)#exit
12-38
Switch2#config
Switch2(config)#port-group 2
Switch2(config)#interface ethernet 1/6
Switch2 (Config-If-Ethernet1/6)#port-group 2 mode on
Switch2 (Config-If-Ethernet1/6)#exit
Switch2 (config)#interface ethernet 1/8-10
Switch2(Config-If-Port-Range)#port-group 2 mode on
Switch2(Config-If-Port-Range)#exit
Configuration result:
Add ports 1, 2, 3, 4 of S1 to port-group1 in order, and we can see a group in “on” mode is
completely joined forcedly, switch in other ends won’t exchange LACP PDU to complete
aggregation. Aggregation finishes immediately when the command to add port 1/2 to
port-group 1 is entered, port 1 and port 2 aggregate to be port-channel 1, when port 1/3 joins
port-group 1, port-channel 1 of port 1 and 2 are ungrouped and re-aggregate with port 3 to
form port-channel 1, when port 1/4 joins port-group 1, port-channel 1 of port 1, 2 and 3 are
ungrouped and re-aggregate with port 4 to form port-channel 1. (It should be noted that
whenever a new port joins in an aggregated port group, the group will be ungrouped first and
re-aggregated to form a new group.) Now all four ports in both S1 and S2 are aggregated in
“on” mode and become an aggregated port respectively.
12.4 Port Channel Troubleshooting
If problems occur when configuring port aggregation, please first check the following for
causes.
Ensure all ports in a port group have the same properties, i.e., whether they are in
full-duplex mode, forced to the same speed, and have the same VLAN properties, etc. If
inconsistency occurs, make corrections.
Some commands cannot be used on a port in port-channel, such as arp, bandwidth, ip,
ip-forward, etc.
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Chapter 13 MTU Configuration
13.1 Introduction to MTU
So far the Jumbo (Jumbo Frame) has not reached a determined standard in the industry
(including the format and length of the frame). Normally frames sized within 1519-9000 should
be considered jumbo frame. Networks with jumbo frames will increase the speed of the whole
network by 2% to 5%. Technically the Jumbo is just a lengthened frame sent and received by
the switch. However considering the length of Jumbo frames, they will not be sent to CPU. We
discard the Jumbo frames sent to CPU in the packet receiving process.
13.2 MTU Configuration Task Sequence
1. Configure enable MTU function
1. Configure enable MTU function
Command Explanation
Global Mode
mtu [<mtu-value>]
no mtu enable
Configure the MTU size of JUMBO frame,
enable the receiving/sending function of
JUMBO frame. The no command disables
sending and receiving function of MTU
frames.
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Chapter 14 EFM OAM Configuration
14.1 Introduction to EFM OAM
Ethernet is designed for Local Area Network at the beginning, but link length and network
scope is extended rapidly while Ethernet is also applied to Metropolitan Area Network and
Wide Area Network along with development. Due to lack the effectively management
mechanism, it affects Ethernet application to Metropolitan Area Network and Wide Area
Network, implementing OAM on Ethernet becomes a necessary development trend.
There are four protocol standards about Ethernet OAM, they are 802.3ah (EFM OAM),
802.3ag (CFM), E-LMI and Y.1731. EFM OAM and CFM are set for IEEE organization. EFM
OAM works in data link layer to validly discover and manage the data link status of rock-bottom.
Using EFM OAM can effectively advance management and maintenance for Ethernet to
ensure the stable network operation. CFM is used for monitoring the whole network
connectivity and locating the fault in access aggregation network layer. Compare with CFM,
Y.1731 standard set by ITU (International Telecommunications Union) is more powerful. E-LMI
standard set by MEF is only applied to UNI. So above protocols can be used to different
network topology and management, between them exist the complementary relation.
EFM OAM (Ethernet in the First Mile Operation, Administration and Maintenance) works in
data link layer of OSI model to implement the relative functions through OAM sublayer, figure
is shown below:
Figure 14-1: OAM location in OSI model
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OAM protocol data units (OAMPDU) use destination MAC address 01-80-c2-00-00-02 of
protocol, the max. transmission rate is 10Pkt/s.
EFM OAM is established on the basis of OAM connection, it provides a link operation
management mechanism such as link monitoring, remote fault detection and remote loopback
testing, the simple introduction for EFM OAM in the following:
1. Ethernet OAM connection establishment
Ethernet OAM entity discovers remote OAM entities and establishes sessions with them by
exchanging Information OAMPDUs. EFM OAM can operate in two modes: active mode and
passive mode. One session can only be established by the OAM entity working in the active
mode and ones working in the passive mode need to wait until it receives the connection
request. After an Ethernet OAM connection is established, the Ethernet OAM entities on both
sides exchange Information OAMPDUs continuously to keep the valid Ethernet OAM
connection. If an Ethernet OAM entity receives no Information OAMPDU for five seconds, the
Ethernet OAM connection is disconnected.
2. Link Monitoring
Fault detection in an Ethernet is difficult, especially when the physical connection in the
network is not disconnected but network performance is degrading gradually. Link monitoring
is used to detect and discover link faults in various environments. EFM OAM implements link
monitoring through the exchange of Event Notification OAMPDUs. When detecting a link error
event, the local OAM entity sends an Event Notification OAMPDU to notify the remote OAM
entity. At the same time it will log information and send SNMP Trap to the network
management system. While OAM entity on the other side receives the notification, it will also
log and report it. With the log information, network administrators can keep track of network
status in time.
The link event monitored by EFM OAM means that the link happens the error event, including
Errored symbol period event, Errored frame event, Errored frame period event, Errored frame
seconds event.
Errored symbol period event: The errored symbol number can not be less than the low
threshold. (Symbol: the min data transmission unit of physical medium. It is unique for coding
system, the symbols may be different for different physical mediums, symbol rate means the
changed time of electron status per second. )
Errored frame period event: Specifying N is frame period, the errored frame number within the
period of receiving N frames can not be less than the low threshold. (Errored frame: Receiving
the errored frame detected by CRC.)
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Errored frame event: The number of detected error frames over M seconds can not be less
than the low threshold.
Errored frame seconds event: The number of error frame seconds detected over M seconds
can not be less than the low threshold. (Errored frame second: Receiving an errored frame at
least in a second.)
3. Remote Fault Detection
In a network where traffic is interrupted due to device failures or unavailability, the flag field
defined in Ethernet OAMPDUs allows an Ethernet OAM entity to send fault information to its
peer. As Information OAMPDUs are exchanged continuously across established OAM
connections, an Ethernet OAM entity can inform one of its OAM peers of link faults through
Information OAMPDUs. Therefore, the network administrator can keep track of link status in
time through the log information and troubleshoot in time.
There are three kinds of link faults for Information OAMPDU, they are Critical Event, Dying
Gasp and Link Fault, and their definitions are different for each manufacturer, here the
definitions are as below:
Critical Event: EFM OAM function of port is disabled.
Link Fault: The number of unidirectional operation or fault can not be less than the high
threshold in local. Unidirectional Operation means unidirectional link can not work normally on
full-duplex link without auto-negotiation. EFM OAM can detect the fault and inform the remote
OAM peers through sending Information OAMPDU.
Dying Gasp: There is no definition present. Although device does not generate Dying Gasp
OAMPDU, it still receives and processes such OAMPDU sent by its peer.
4. Remote loopback testing
Remote loopback testing is available only after an Ethernet OAM connection is established.
With remote loopback enabled, operating Ethernet OAM entity in active mode issues remote
loopback requests and the peer responds to them. If the peer operates in loopback mode, it
returns all packets except Ethernet OAMPDUs to the senders along the original paths.
Performing remote loopback testing periodically helps to detect network faults in time.
Furthermore, performing remote loopback testing by network segments helps to locate
network faults. Note: The communication will not be processed normally in remote loopback
mode.
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Shown below is the typical EFM OAM application topology. It is used for point-to-point link and
emulational IEEE 802.3 point-to-point link. Device enables EFM OAM through point-to-point
connection to monitor the link fault in the First Mile with Ethernet access. For user, the
connection between user to telecommunication is “the First Mile”, for service provider, it is “the
Last Mile”.
Customer Service Provider Customer
CE PE802.1ah OAMPDU
802.3ah Ethernet in the First Mile
Figure 14-2: Typical OAM application topology
14.2 EFM OAM Configuration
EFM OAM configuration task list
1. Enable EFM OAM function of port
2. Configure link monitor
3. Configure remote failure
Note: it needs to enable OAM first when configuring OAM parameters.
1. Enable EFM OAM function of port
Command Explanation
Port Mode
ethernet-oam mode {active | passive} Configure work mode of EFM OAM,
default is active mode.
ethernet-oam
no ethernet-oam
Enable EFM OAM of port, no
command disables EFM OAM of
port.
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ethernet-oam period <seconds>
no ethernet-oam period
Configure transmission period of
OAMPDU (optional), no command
restores the default value.
ethernet-oam timeout <seconds>
no ethernet-oam timeout
Configure timeout of EFM OAM
connection, no command restores
the default value.
2. Configure link monitor
Command Explanation
Port Mode
ethernet-oam link-monitor
no ethernet-oam link-monitor
Enable link monitor of EFM OAM, no
command disables link monitor.
ethernet-oam errored-symbol-period
{threshold low <low-symbols> | window
<seconds>}
no ethernet-oam errored-symbol-period
{threshold low | window }
Configure the low threshold and
window period of errored symbol
period event, no command restores
the default value. (optional)
ethernet-oam errored-frame-period {threshold
low <low-frames> | window <seconds>}
no ethernet-oam errored-frame-period
{threshold low | window }
Configure the low threshold and
window period of errored frame
period event, no command restores
the default value.
ethernet-oam errored-frame {threshold low
<low-frames> | window <seconds>}
no ethernet-oam errored-frame {threshold low
| window }
Configure the low threshold and
window period of errored frame
event, no command restores the
default value. (optional)
ethernet-oam errored-frame-seconds
{threshold low <low-frame-seconds> | window
<seconds>}
no ethernet-oam errored-frame-seconds
{threshold low | window }
Configure the low threshold and
window period of errored frame
seconds event, no command
restores the default value. (optional)
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3. Configure remote failure
Command Explanation
Port Mode
ethernet-oam remote-failure
no ethernet-oam remote-failure
Enable remote failure detection of
EFM OAM (failure means
critical-event or link-fault event of the
local), no command disables the
function. (optional)
ethernet-oam errored-symbol-period
threshold high {high-symbols | none}
no ethernet-oam errored-symbol-period
threshold high
Configure the high threshold of
errored symbol period event, no
command restores the default value.
(optional)
ethernet-oam errored-frame-period threshold
high {high-frames | none}
no ethernet-oam errored-frame-period
threshold high
Configure the high threshold of
errored frame period event, no
command restores the default value.
(optional)
ethernet-oam errored-frame threshold high
{high-frames | none}
no ethernet-oam errored-frame threshold high
Configure the high threshold of
errored frame event, no command
restores the default value. (optional)
ethernet-oam errored-frame-seconds
threshold high {high-frame-seconds | none}
no ethernet-oam errored-frame-seconds
threshold high
Configure the high threshold of
errored frame seconds event, no
command restores the default value.
(optional)
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14.3 EFM OAM Example
Example:
CE and PE devices with point-to-point link enable EFM OAM to monitor “the First Mile” link
performance. It will report the log information to network management system when occurring
fault event and use remote loopback function to detect the link in necessary instance
Figure 14-3: Typical OAM application topology
Configuration procedure: (Omitting SNMP and Log configuration in the following)
Configuration on CE:
CE(config)#interface ethernet1/1
CE (config-if-ethernet1/1)#ethernet-oam mode passive
CE (config-if-ethernet1/1)#ethernet-oam
CE (config-if-ethernet1/1)#ethernet-oam remote-loopback supported
Other parameters use the default configuration.
Configuration on PE:
PE(config)#interface ethernet 1/1
PE (config-if-ethernet1/1)#ethernet-oam
Other parameters use the default configuration.
Execute the following command when using remote loopback.
PE(config-if-ethernet1/1)#ethernet-oam remote-loopback
Execute the following command to make one of OAM peers exiting OAM loopback after
complete detection.
PE(config-if-ethernet1/1)# no ethernet-oam remote-loopback
Execute the following command without supporting remote loopback.
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CE(config-if-ethernet1/1)#no ethernet-oam remote-loopback supported
14.4 EFM OAM Troubleshooting
When using EFM OAM, it occurs the problem, please check whether the problem is resulted
by the following reasons:
Check whether OAM entities of two peers of link in passive mode. If so, EFM OAM
connection can not be established between two OAM entities.
Ensuring SNMP configuration is correct, or else errored event can not be reported to
network management system.
Link does not normally communicate in OAM loopback mode, it should cancel
remote loopback in time after detect the link performance.
Ensuring the used board supports remote loopback function.
Port should not configure STP, MRPP, ULPP, Flow Control, loopback detection
functions after it enables OAM loopback function, because OAM remote loopback
function and these functions are mutually exclusive.
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Chapter 15 PORT SECURITY
15.1 Introduction to PORT SECURITY
Port security is a MAC address-based security mechanism for network access controlling. It is
an extension to the existing 802.1x authentication and MAC authentication. It controls the
access of unauthorized devices to the network by checking the source MAC address of the
received frame and the access to unauthorized devices by checking the destination MAC
address of the sent frame. With port security, you can define various port security modes to
make that a device learns only legal source MAC addresses, so as to implement
corresponding network security management. After port security is enabled, the device detects
an illegal frame, it triggers the corresponding port security feature and takes a pre-defined
action automatically. This reduces user’s maintenance workload and greatly enhances system
security.
15.2 PORT SECURITY Configuration Task List
1. Basic configuration for PORT SECURITY
Command Explanation
Port Mode
switchport port-security
no switchport port-security
Configure port-security of the
interface.
switchport port-security mac-address
<mac-address> [vlan <vlan-id>]
no switchport port-security mac-address
<mac-address> [vlan <vlan-id>]
Configure the static security
MAC of the interface.
switchport port-security maximum <value> [vlan
<vlan-list>]
no switchport port-security maximum <value> [vlan
<vlan-list>]
Configure the maximum
number of the security MAC
address allowed by the
interface.
switchport port-security violation {protect | restrict |
shutdown}
no switchport port-security violation
When exceeding the maximum
number of the configured MAC
addresses, MAC address
accessing the interface does
not belongs to this interface in
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MAC address table or a MAC
address is configured to
several interfaces in same
VLAN, both of them will violate
the security of the MAC
address.
switchport port-security aging {static | time <value>
| type {absolute | inactivity}}
no switchport port-security violation aging {static |
time | type}
Enable port-security aging
entry of the interface, specify
aging time or aging type.
Admin Mode
clear port-security {all | configured | dynamic |
sticky} [[address <mac-addr> | interface
<interface-id>] [vlan <vlan-id> ]]
Clear the secure MAC entry of
the interface.
show port-security [interface <interface-id>]
[address | vlan]
Show port-security
configuration.
15.3 Example of PORT SECURITY
Internet
Figure 15-1: Typical topology chart for port security
When the interface enables Port security function, configure the maximum number of the
secure MAC addresses allowed by an interface to be 10, the interface allows 10 users to
access the internet at most. If it exceeds the maximum number, the new user cannot access
the internet, so that it not only limits the user’s number but also accesses the internet safely. If
configuring the maximum number of the secure MAC addresses as 1, only HOST A or HOST B
is able to access the internet.
Configuration process:
#Configure the switch.
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Switch(config)#interface Ethernet 1/1
Switch(config-if-ethernet1/1)#switchport port-security
Switch(config-if- ethernet1/1)#switchport port-security maximum 10
Switch(config-if- ethernet1/1)#exit
Switch(config)#
15.4 PORT SECURITY Troubleshooting
If problems occur when configuring PORT SECURITY, please check whether the problem is
caused by the following reasons:
Check whether PORT SECURITY is enabled normally
Check whether the valid maximum number of MAC addresses is configured
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Chapter 16 DDM Configuration
16.1 Introduction to DDM
16.1.1 Brief Introduction to DDM
DDM (Digital Diagnostic Monitor) makes the detailed digital diagnostic function standard in
SFF-8472 MSA. It sets that the parameter signal is monitored and makes it to digitize on the
circuit board of the inner module. After that, providing the demarcated result or the digitize
measure result and the demarcated parameter which are saved in the standard memory
framework, so as to expediently read by serial interface with double cables.
Normally, intelligent fiber modules support Digital Diagnostic function. Network management
unit is able to monitor the parameters (temperature, voltage, bias current, tx power and rx
power) of the fiber module to obtain their thresholds and the real-time state of the current fiber
module by the inner MCU of the fiber module. That is able to help the network management
units to locate the fault in the fiber link, reduce the maintenance workload and enhance the
system reliability.
DDM applications are shown in the following:
1. Module lifetime forecast
Monitoring the bias current is able to forecast the laser lifetime. Administrator is able to find
some potential problems by monitoring voltage and temperature of the module.
（1）High Vcc voltage will result in the breakdown CMOS, low Vcc voltage will result in the
abnormity work.
（2）High rx power will damage the receiving module, low rx power will result that the
receiving module cannot work normally.
（3）High temperature will result in the fast aging of the hardware.
（4）Monitoring the received fiber power to monitor the capability of the link and the remote
switch.
2. Fault location
In fiber link, locating the fault is important to the fast overload of the service, fault isolation is
able to help administrator to fast locate the location of the link fault within the module (local
module or remote module) or on the link, it also reduce the time for restoring the fault of the
system.
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Analyzing warning and alarm status of real-time parameters (temperature, voltage, bias
current, tx power and rx power) can fast locate the fault through Digital Diagnostic function.
Besides, the state of Tx Fault and Rx LOS is important for analyzing the fault.
3. Compatibility verification
Compatibility verification is used to analyze whether the environment of the module accords
the data manual or it is compatible with the corresponding standard, because the module
capability is able to be ensured only in the compatible environment. Sometimes, environment
parameters exceed the data manual or the corresponding standard, it will make the falling of
the module capability that result in the transmission error.
Environment is not compatible with the module are as below:
（1）Voltage exceeds the set range
（2）Rx power is overload or is under the sensitivity of the transceiver
（3）Temperature exceeds the range of the running temperature
SGS-6340-20S4C4X doesn’t support DDM function.
16.1.2 DDM Function
DDM descriptions are shown in the following:
1. Show the monitoring information of the transceiver
Administrator is able to know the current working state of the transceiver and find some
potential problems through checking the real-time parameters (including TX power, RX power,
Temperature, Voltage, Bias current) and querying the monitoring information (such as warning,
alarm, real-time state and threshold, and so on). Besides, checking the fault information of the
fiber module helps administrator to fast locate the link fault and saves the restored time.
2. Threshold defined by the user
For real-time parameters (TX power, RX power, Temperature, Voltage, Bias current), there are
fixed thresholds. Because the user’s environments are difference, the users is able to define
the threshold (including high alarm, low alarm, high warn, low warn) to flexibly monitor the
working state of the transceiver and find the fault directly.
The thresholds configured by the user and the manufacturer can be shown at the same time.
When the threshold defined by the user is irrational, it will prompt the user and automatically
16-53
process alarm or warning according to the default threshold. (the user is able to restore all
thresholds to the default thresholds or restore a threshold to the default threshold)
Threshold rationality: high/low warn should be between high alarm and low alarm and high
threshold should be higher than low threshold, namely, high alarm>= high warn>= low warn>=
low alarm.
For fiber module, verification mode of the receiving power includes inner verification and outer
verification which are decided by the manufacturer. Besides the verification mode of the
real-time parameters and the default thresholds are same.
3. Transceiver monitoring
Besides checking the real-time working state of the transceiver, the user needs to monitor the
detailed status, such as the former abnormity time and the abnormity type. Transceiver
monitoring helps the user to find the former abnormity status through checking the log and
query the last abnormity status through executing the commands. When the user finds the
abnormity information of the fiber module, the fiber module information may be remonitored
after processing the abnormity information, here, the user is able to know the abnormity
information and renew the monitoring.
16.2 DDM Configuration Task List
DDM configuration task list:
1. Show the real-time monitoring information of the transceiver
2. Configure the alarm or warning thresholds of each parameter for the transceiver
3. Configure the state of the transceiver monitoring
（1） Configure the interval of the transceiver monitoring
（2） Configure the enable state of the transceiver monitoring
（3） Show the information of the transceiver monitoring
（4） Clear the information of the transceiver monitoring
1. Show the real-time monitoring information of the transceiver
Command Explanation
Admin and Global Mode
show transceiver [interface ethernet
<interface-list>][detail]
Show the monitoring of the
transceiver.
2. Configure the alarm or warning thresholds of each parameter for the transceiver
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Command Explanation
Port Mode
transceiver threshold {default | {temperature |
voltage | bias | rx-power | tx-power}
{high-alarm | low-alarm | high-warn |
low-warn} {<value> | default}}
Set the threshold defined by the
user.
3. Configure the state of the transceiver monitoring
(1) Configure the interval of the transceiver monitoring
Command Explanation
Global Mode
transceiver-monitoring interval <minutes>
no transceiver-monitoring interval
Set the interval of the transceiver
monitor. The no command sets the
interval to be the default interval of
15 minutes.
（2）Configure the enable state of the transceiver monitoring
Command Explanation
Port Mode
transceiver-monitoring {enable | disable}
Set whether the transceiver
monitoring is enabled. Only the port
enables the transceiver monitoring,
the system records the abnormity
state. After the port disables the
function, the abnormity information
will be clear.
（3）Show the information of the transceiver monitoring
Command Explanation
Admin and Global Mode
show transceiver threshold-violation
[interface ethernet <interface-list>]
Show the information of the
transceiver monitoring, including the
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last threshold-violation information,
the interval of the current transceiver
monitoring and whether the port
enables the transceiver monitoring.
（4）Clear the information of the transceiver monitoring
Command Explanation
Admin Mode
clear transceiver threshold-violation [interface
ethernet <interface-list>]
Clear the threshold violation of the
transceiver monitor.
16.3 Examples of DDM
Example1:
Ethernet 21 and Ethernet 23 are inserted the fiber module with DDM, Ethernet 24 is inserted
the fiber module without DDM, Ethernet 22 does not insert any fiber module, show the DDM
information of the fiber module.
a、Show the information of all interfaces which can read the real-time parameters normally,(No
fiber module is inserted or the fiber module is not supported, the information will not be shown),
for example:
Switch#show transceiver
Interface Temp（℃） Voltage（V） Bias（mA） RX Power（dBM） TX Power
（dBM）
1/21 33 3.31 6.11 -30.54(A-) -6.01
1/23 33 5.00（W+） 6.11 -20.54(W-) -6.02
b、Show the information of the specified interface. (N/A means no fiber module is inserted or
does not support the fiber module), for example:
Switch#show transceiver interface ethernet 1/21-22;23
Interface Temp（℃） Voltage（V） Bias（mA） RX Power（dBM） TX Power（dBM）
1/21 33 3.31 6.11 -30.54(A-) -6.01
1/22 N/A N/A N/A N/A N/A
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1/23 33 5.00（W+） 6.11 -20.54(W-) -6.02
c、Show the detailed information, including base information, parameter value of the real-time
monitoring, warning, alarm, abnormity state and threshold information, for example:
Switch#show transceiver interface ethernet 1/21-22;24 detail
Ethernet 1/21 transceiver detail information:
Base information:
SFP found in this port, manufactured by company, on Sep 29 2010.
Type is 1000BASE-SX, Link length is 550 m for 50um Multi-Mode Fiber.
Link length is 270 m for 62.5um Multi-Mode Fiber.
Nominal bit rate is 1300 Mb/s, Laser wavelength is 850 nm.
Brief alarm information:
RX loss of signal
Voltage high
RX power low
Detail diagnostic and threshold information:
Diagnostic Threshold
Realtime Value High Alarm Low Alarm High Warn Low Warn
-------------- ----------- ----------- ------------ ---------
Temperature（℃） 33 70 0 70 0
Voltage（V） 7.31(A+) 5.00 0.00 5.00 0.00
Bias current（mA） 6.11(W+) 10.30 0.00 5.00 0.00
RX Power（dBM） -30.54(A-) 9.00 -25.00 9.00 -25.00
TX Power（dBM） -6.01 9.00 -25.00 9.00 -25.00
Ethernet 1/22 transceiver detail information: N/A
Ethernet 1/24 transceiver detail information:
Base information:
SFP found in this port, manufactured by company, on Sep 29 2010.
Type is 1000BASE-SX, Link length is 550 m for 50um Multi-Mode Fiber.
Link length is 270 m for 62.5um Multi-Mode Fiber.
Nominal bit rate is 1300 Mb/s, Laser wavelength is 850 nm.
Brief alarm information: N/A
Detail diagnostic and threshold information: N/A
Example 2:
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Ethernet 21 is inserted the fiber module with DDM. Configure the threshold of the fiber module
after showing the DDM information.
Step 1: Show the detailed DDM information.
Switch#show transceiver interface ethernet 1/21 detail
Ethernet 1/21 transceiver detail information:
Base information:
……
Brief alarm information:
RX loss of signal
Voltage high
RX power low
Detail diagnostic and threshold information:
Diagnostic Threshold
Realtime Value High Alarm Low Alarm High Warn Low Warn
-------------- ----------- ----------- ------------ ---------
Temperature（℃） 33 70 0 70 0
Voltage（V） 7.31(A+) 5.00 0.00 5.00 0.00
Bias current（mA） 6.11(W+) 10.30 0.00 5.00 0.00
RX Power（dBM） -30.54(A-) 9.00 -25.00 9.00 -25.00
TX Power（dBM） -13.01 9.00 -25.00 9.00 -25.00
Step 2: Configure the tx-power threshold of the fiber module, the low-warning threshold is -12,
the low-alarm threshold is -10.00.
Switch#config
Switch(config)#interface ethernet 1/21
Switch(config-if-ethernet1/21)#transceiver threshold tx-power low-warning -12
Switch(config-if-ethernet1/21)#transceiver threshold tx-power low-alarm -10.00
Step 3: Show the detailed DDM information of the fiber module. The alarm uses the threshold
configured by the user, the threshold configured by the manufacturer is labeled with the
bracket. There is the alarm with ‘A-’ due to -13.01 is less than -12.00.
Switch#show transceiver interface ethernet 1/21 detail
Ethernet 1/21 transceiver detail information:
Base information:
……
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Brief alarm information:
RX loss of signal
Voltage high
RX power low
TX power low
Detail diagnostic and threshold information:
Diagnostic Threshold
Realtime Value High Alarm Low Alarm High Warn Low Warn
-------------- ----------- ----------- ---------- ---------
Temperature（℃） 33 70 0 70 0
Voltage（V） 7.31(A+) 5.00 0.00 5.00 0.00
Bias current（mA） 6.11(W+) 10.30 0.00 5.00 0.00
RX Power（dBM） -30.54(A-) 9.00 -25.00 9.00 -25.00
TX Power（dBM） -13.01(A-) 9.00 -12.00(-25.00) 9.00 -10.00(-25.00)
Example 3:
Ethernet 21 is inserted the fiber module with DDM. Enable the transceiver monitoring of the
port after showing the transceiver monitoring of the fiber module.
Step 1: Show the transceiver monitoring of the fiber module. Both ethernet 21 and ethernet 22
do not enable the transceiver monitoring, its interval is set to 30 minutes.
Switch(config)#show transceiver threshold-violation interface ethernet 1/21-22
Ethernet 1/21 transceiver threshold-violation information:
Transceiver monitor is disabled. Monitor interval is set to 30 minutes.
The last threshold-violation doesn’t exist.
Ethernet 1/22 transceiver threshold-violation information:
Transceiver monitor is disabled. Monitor interval is set to 30 minutes.
The last threshold-violation doesn’t exist.
Step 2: Enable the transceiver monitoring of ethernet 21.
Switch(config)#interface ethernet 1/21
Switch(config-if-ethernet1/21)#transceiver-monitoring enable
Step 3: Show the transceiver monitoring of the fiber module. In the following configuration,
ethernet 21 enabled the transceiver monitoring, the last threshold-violation time is Jan 02
11:00:50 2011, the detailed DDM information exceeding the threshold is also shown.
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Switch(config-if-ethernet1/21)#quit
Switch(config)#show transceiver threshold-violation interface ethernet 1/21-22
Ethernet 1/21 transceiver threshold-violation information:
Transceiver monitor is enabled. Monitor interval is set to 30 minutes.
The current time is Jan 02 12:30:50 2011.
The last threshold-violation time is Jan 02 11:00:50 2011.
Brief alarm information:
RX loss of signal
RX power low
Detail diagnostic and threshold information:
Diagnostic Threshold
Realtime Value High Alarm Low Alarm High Warn Low Warn
------------ ----------- ----------- ------------ ---------
Temperature（℃） 33 70 0 70 0
Voltage（V） 7.31 10.00 0.00 5.00 0.00
Bias current（mA） 3.11 10.30 0.00 5.00 0.00
RX Power（dBM） -30.54(A-) 9.00 -25.00(-34) 9.00 -25.00
TX Power（dBM） -1.01 9.00 -12.05 9.00 -10.00
Ethernet 1/22 transceiver threshold-violation information:
Transceiver monitor is disabled. Monitor interval is set to 30 minutes.
The last threshold-violation doesn’t exist.
16.4 DDM Troubleshooting
If problems occur when configuring DDM, please check whether the problem is caused by the
following reasons:
Ensure that the transceiver of the fiber module has been inserted fast on the port, or
else DDM configuration will not be shown.
Ensure that SNMP configuration is valid, or else the warning event cannot inform the
network management system.
Because only some boards and box switches support SFP with DDM or XFP with
DDM, ensure the used board and switch support the corresponding function.
When using show transceiver command or show transceiver detail command, it
cost much time due to the switch will check all ports, so it is recommended to query
the monitoring information of the transceiver on the specified port.
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Ensure the threshold defined by the user is valid. When any threshold is error, the
transceiver will give an alarm according to the default setting automatically.
Chapter 17 LLDP-MED
17.1 Introduction to LLDP-MED
LLDP-MED (Link Layer Discovery Protocol-Media Endpoint Discovery) based on 802.1AB
LLDP (Link Layer Discovery Protocol) of IEEE. LLDP provides a standard link layer discovery
mode, it sends local device information (including its major capability, management IP address,
device ID and port ID) as TLV (type/length/value) triplets in LLDPDU (Link Layer Discovery
Protocol Data Unit) to the direct connection neighbors. The device information received by the
neighbors will be stored with a standard management information base (MIB). This allows a
network management system to quickly detect and identify the communication status of the
link.
In 802.1AB LLDP, there is no transmission and management about the voice device
information. To deploy and manage voice device expediently, LLDP-MED TLVs provide
multiple information, such as PoE (Power over Ethernet), network policy, and the location
information of the emergent telephone service.
17.2 LLDP-MED Configuration Task Sequence
1. Basic LLDP-MED configuration
Command Explanation
Port Mode
lldp transmit med tlv all
no lldp transmit med tlv all
Configure the specified port to
send all LLDP-MED TLVs. The
no command disables the
function.
lldp transmit med tlv capability Configure the specified port to
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no lldp transmit med tlv capability send LLDP-MED Capability
TLV. The no command
disables the capability.
lldp transmit med tlv networkPolicy
no lldp transmit med tlv networkPolicy
Configure the specified port to
send LLDP-MED Network
Policy TLV. The no command
disables the capability.
lldp transmit med tlv extendPoe
no lldp transmit med tlv extendPoe
Configure the specified port to
send LLDP-MED Extended
Power-Via-MDI TLV. The no
command disables the
capability.
lldp transmit med tlv inventory
no lldp transmit med tlv inventory
Configure the port to send
LLDP-MED Inventory
Management TLVs. The no
command disables the
capability.
network policy {voice | voice-signaling | guest-voice
| guest-voice-signaling | softphone-voice |
video-conferencing | streaming-video |
video-signaling} [status {enable | disable}] [tag
{tagged | untagged}] [vid {<vlan-id> | dot1p}] [cos
<cos-value>] [dscp <dscp-value> ]
no network policy {voice | voice-signaling |
guest-voice | guest-voice-signaling |
softphone-voice | video-conferencing | streaming-
video | video-signaling}
Configure network policy of the
port, including VLAN ID, the
supported application (such as
voice and video), the
application priority and the
used policy, and so on.
civic location {dhcp server | switch | endpointDev}
<country-code>
no civic location
Configure device type and
country code of the location
with Civic Address LCI format
and enter Civic Address LCI
address mode. The no
command cancels all
configurations of the location
with Civic Address LCI format.
ecs location <tel-number>
no ecs location
Configure the location with
ECS ELIN format on the port,
the no command cancels the
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configured location.
lldp med trap {enable | disable} Enable or disable LLDP-MED
trap for the specified port.
Civic Address LCI address Mode
{description-language | province-state | city | county
| street | locationNum | location | floor | room |
postal | otherInfo} <address>
no {description-language | province-state | city |
county | street | locationNum | location | floor | room
| postal | otherInfo}
Configure the detailed address
after enter Civic Address LCI
address mode of the port.
Global Mode
lldp med fast count <value>
no lldp med fast count
When the fast LLDP-MED
startup mechanism is enabled,
it needs to fast send the LLDP
packets with LLDP-MED TLV,
this command is used to set
the value of the fast sending
packets, the no command
restores the default value.
Admin Mode
show lldp Show the configuration of the
global LLDP and LLDP-MED.
show lldp [interface ethernet <IFNAME>]
Show the configuration of
LLDP and LLDP-MED on the
current port.
show lldp neighbors [interface ethernet <IFNAME>]Show LLDP and LLDP-MED
configuration of the neighbors.
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17.3 LLDP-MED Example
Figure 17-1: Basic LLDP-MED configuration topology
1) Configure Switch A
SwitchA(config)#interface ethernet1/1
SwitchA (Config-If-Ethernet1/1)# lldp enable
SwitchA (Config-If-Ethernet1/1)# lldp mode both（this configuration can be omitted, the
default mode is RxTx）
SwitchA (Config-If-Ethernet1/1)# lldp transmit med tlv capability
SwitchA (Config-If-Ethernet1/1)# lldp transmit med tlv network policy
SwitchA (Config-If-Ethernet1/1)# lldp transmit med tlv inventory
SwitchB (Config-If-Ethernet1/1)# network policy voice tag tagged vid 10 cos 5 dscp 15
SwitchA (Config-If-Ethernet1/1)# exit
SwitchA (config)#interface ethernet1/2
SwitchA (Config-If-Ethernet1/2)# lldp enable
SwitchA (Config-If-Ethernet1/2)# lldp mode both
2) Configure Switch B
SwitchB (config)#interface ethernet1/1
SwitchB(Config-If-Ethernet1/1)# lldp enable
SwitchB (Config-If-Ethernet1/1)# lldp mode both
SwitchB (Config-If-Ethernet1/1)# lldp transmit med tlv capability
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SwitchB (Config-If-Ethernet1/1)# lldp transmit med tlv network policy
SwitchB (Config-If-Ethernet1/1)# lldp transmit med tlv inventory
SwitchB (Config-If-Ethernet1/1)# network policy voice tag tagged vid 10 cos 4
3) Verify the configuration
# Show the global status and interface status on Switch A.
SwitchA# show lldp neighbors interface ethernet 1/1
Port name : Ethernet1/1
Port Remote Counter : 1
TimeMark :20
ChassisIdSubtype :4
ChassisId :00-30-4f-00-00-02
PortIdSubtype :Local
PortId :1
PortDesc :****
SysName :****
SysDesc :*****
SysCapSupported :4
SysCapEnabled :4
LLDP MED Information :
MED Codes:
(CAP)Capabilities, (NP) Network Policy
(LI) Location Identification, (PSE)Power Source Entity
(PD) Power Device, (IN) Inventory
MED Capabilities:CAP,NP,PD,IN
MED Device Type: Endpoint Class III
Media Policy Type :Voice
Media Policy :Tagged
Media Policy Vlan id :10
Media Policy Priority :3
Media Policy Dscp :5
Power Type : PD
Power Source :Primary power source
Power Priority :low
Power Value :15.4 (Watts)
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Hardware Revision:
Firmware Revision:4.0.1
Software Revision:6.2.30.0
Serial Number:
Manufacturer Name:****
Model Name:Unknown
Assert ID:Unknown
IEEE 802.3 Information :
auto-negotiation support: Supported
auto-negotiation support: Not Enabled
PMD auto-negotiation advertised capability: 1
operational MAU type: 1
SwitchA# show lldp neighbors interface ethernet 1/2
Port name : interface ethernet 1/2
Port Remote Counter：1
Neighbor Index: 1
Port name : Ethernet1/2
Port Remote Counter : 1
TimeMark :20
ChassisIdSubtype :4
ChassisId :00-30-4f-00-00-02
PortIdSubtype :Local
PortId :1
PortDesc :Ethernet1/1
SysName :****
SysDesc :*****
SysCapSupported :4
SysCapEnabled :4
Explanation:
1) Both Ethernet2 of switch A and Ethernet1 of switch B are the ports of network connection
device, they will not send LLDP packets with MED TLV information forwardly. Although
configure Ethernet1 of switch B to send MED TLV information, it will not send the related MED
information, that results the corresponding Remote table without the related MDE information
on Ethernet2 of switch A.
2) LLDP-MED device is able to send LLDP packets with MED TLV forwardly, so the
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corresponding Remote table with LLDP MED information on Ethernet1 of switch A.
17.4 LLDP-MED Troubleshooting
If problems occur when configuring LLDP-MED, please check whether the problem is caused
by the following reasons:
Check whether the global LLDP is enabled.
Only network connection device received LLDP packets with LLDP-MED TLV from
the near MED device, it sends LLDP-MED TLV. If network connection device
configured the command for sending LLDP-MED TLV, the packets also without
LLDP-MED TLV sent by the port, that means no MED information is received and
the port does not enable the function for sending LLDP-MED information.
If neighbor device has sent LLDP-MED information to network connection device,
but there is no LLDP-MED information by checking show lldp neighbors command,
that means LLDP-MED information sent by neighbor is error.
Chapter 18 bpdu-tunnel Configuration
18.1 Introduction to bpdu-tunnel
BPDU Tunnel is a Layer 2 tunnel technology. It allows Layer 2 protocol packets of
geographically dispersed private network users to be transparently transmitted over specific
tunnels across a service provider network.
18.1.1 bpdu-tunnel function
In MAN application, multi-branches of a corporation may connect with each other by the
service provider network. VPN provided by the service provider enables the geographically
dispersed networks to form a local LAN, so the service provider needs to provide the tunnel
function, namely, data information generated by user’s network is able to arrive at other
networks of the same corporation through the service provider network. To maintain a local
concept, it not only needs to transmit the data within the user’s private network across the
tunnel, but also transmit layer 2 protocol packets within the user’s private network.
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18.1.2 Background of bpdu-tunnel
Special lines are used in a service provider network to build user-specific Layer 2 networks. As
a result, a user network is broken down into parts located at different sides of the service
provider network. As shown in Figure, User A has two devices (CE 1 and CE 2) and both
devices belong to the same VLAN. User’s network is divided into network 1 and network 2,
which are connected by the service provider network. When Layer 2 protocol packets cannot
implement the passthrough across the service provider network, the user’s network cannot
process independent Layer 2 protocol calculation (for example, spanning tree calculation), so
they affect each other.
Figure 18-1: BPDU Tunnel application
18.2 bpdu-tunnel Configuration Task List
bpdu-tunnel configuration task list:
1. Configure tunnel MAC address globally
2. Configure the port to support the tunnel
1. Configure tunnel MAC address globally
Command Explanation
Global Mode
bpdu-tunnel {stp|gvrp|dot1x}
no bpdu-tunnel {stp|gvrp|dot1x}
Enable to support the tunnel, the no
command disables the function.
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2. Configure the port to support the tunnel
Command Explanation
Port Mode
bpdu-tunnel {stp|gvrp|dot1x}
no bpdu-tunnel {stp|gvrp|dot1x}
Enable the port to support the tunnel,
the no command disables the
function.
18.3 Examples of bpdu-tunnel
Special lines are used in a service provider network to build user-specific Layer 2 networks. As
a result, a user network is broken down into parts located at different sides of the service
provider network. As shown in Figure, User A has two devices (CE 1 and CE 2) and both
devices belong to the same VLAN. User’s network is divided into network 1 and network 2,
which are connected by the service provider network. When Layer 2 protocol packets cannot
implement the passthrough across the service provider network, the user’s network cannot
process independent Layer 2 protocol calculation (for example, spanning tree calculation), so
they affect each other.
Figure 18-2: BPDU Tunnel application environment
With BPDU Tunnel, Layer 2 protocol packets from user’s networks can be passed through
over the service provider network in the following work flow:
1. After receiving a Layer 2 protocol packet from network 1 of user A, PE 1 in the service
provider network encapsulates the packet, replaces its destination MAC address with a
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specific multicast MAC address, and then forwards the packet in the service provider network.
2. The encapsulated Layer 2 protocol packet (called BPDU Tunnel packet) is forwarded to PE
2 at the other end of the service provider network, which de-encapsulates the packet, restores
the original destination MAC address of the packet, and then sends the packet to network 2 of
user A.
bpdu-tunnel configuration of edge switches PE1 and PE2 in the following:
PE1 configuration:
PE1(config)# bpdu-tunnel dmac 01-02-03-04-05-06
PE1(config-if-ethernet1/1)# bpdu-tunnel stp
PE1(config-if-etherne1/1)# bpdu-tunnel lacp
PE1(config-if-ethernet1/1)# bpdu-tunnel uldp
PE1(config-if-ethernet1/1)# bpdu-tunnel gvrp
PE1(config-if-ethernet1/1)# bpdu-tunnel dot1x
PE2 configuration:
PE2(config)# bpdu-tunnel dmac 01-02-03-04-05-06
PE2(config-if-ethernet1/1)# bpdu-tunnel stp
PE2(config-if-ethernet1/1)# bpdu-tunnel lacp
PE2(config-if-ethernet1/1)# bpdu-tunnel uldp
PE2(config-if-ethernet1/1)# bpdu-tunnel gvrp
PE2(config-if-ethernet1/1)# bpdu-tunnel dot1x
18.4 bpdu-tunnel Troubleshooting
After port disables stp, gvrp, uldp, lacp and dot1x functions, it is able to configure bpdu-tunnel
function.
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Chapter 19 EEE Energy-saving
Configuration
19.1 Introduction to EEE Energy-saving
eee is Energy Efficient Ethernet. After the port is enabled this function, switch will detect the
port state automatically. If the port is free and there is no data transmission, this port will
change to the power saving mode and it will cut down the power of the port to save the energy.
19.2 EEE Energy-saving configuration List
1. Enable EEE energy-saving function
Command Explanation
Port Mode
eee enable
no eee enable
Enable the energy-saving
function of the port; the no
command disables the
energy-saving function of the
port.
19.3 EEE Energy-saving Typical Examples
Case：Configure the port 1 of switch as saving mode.
Below is the configuration steps:
Switch(config-if-ethernet1/1)# eee enable
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Chapter 20 VLAN Configuration
20.1 VLAN Configuration
20.1.1 Introduction to VLAN
VLAN (Virtual Local Area Network) is a technology that divides the logical addresses of
devices within the network to separate network segments based on functions, applications or
management requirements. By this way, virtual workgroups can be formed regardless of the
physical location of the devices. IEEE announced IEEE 802.1Q protocol to direct the
standardized VLAN implementation, and the VLAN function of switch is implemented following
IEEE 802.1Q.
The key idea of VLAN technology is that a large LAN can be partitioned into many separate
broadcast domains dynamically to meet the demands.
Figure 20-1: A VLAN network defined logically
Each broadcast domain is a VLAN. VLANs have the same properties as the physical LANs,
except VLAN is a logical partition rather than physical one. Therefore, the partition of VLANs
can be performed regardless of physical locations, and the broadcast, multicast and unicast
traffic within a VLAN is separated from the other VLANs.
Switch Switch Switch
VLAN1
Server Server Server
PC VLAN2
PC PC
PC PC Laser Printer
VLAN3
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With the aforementioned features, VLAN technology provides us with the following
conveniences:
Improving network performance
Saving network resources
Simplifying network management
Lowering network cost
Enhancing network security
Switch Ethernet Ports can work in three kinds of modes: Access, Hybrid and Trunk with each
mode having a different processing method in forwarding the packets with tagged or untagged.
The ports of Access type only belong to one VLAN, usually they are used to connect the ports
of the computer.
The ports of Trunk type allow multi-VLANs to pass, receive and send the packets of
multi-VLANs. Usually they are used to connect between the switches.
The ports of Hybrid type allow multi-VLANs to pass, receive and send the packets of
multi-VLANs. They can be used to connect between the switches, or to a computer of the user.
Hybrid ports and Trunk ports receive the data with the same process method, but send the
data with a different method: Hybrid ports can send the packets of multi-VLANs without the
VLAN tag, while Trunk ports send the packets of multi-VLANs with the VLAN tag except the
port native VLAN.
The switch implements VLAN and GVRP (GARP VLAN Registration Protocol) which are
defined by 802.1Q. The chapter will explain the use and the configuration of VLAN and GVRP
in details.
20.1.2 VLAN Configuration Task List
1. Create or delete VLAN
2. Set or delete VLAN name
3. Assign Switch ports for VLAN
4. Set the switch port type
5. Set Trunk port
6. Set Access port
7. Set Hybrid port
8. Enable/Disable VLAN ingress rules globally
9. Configure Private VLAN
10. Set Private VLAN association
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11. Specify internal VLAN ID
1. Create or delete VLAN
Command Explanation
Global Mode
vlan WORD
no vlan WORD Create/delete VLAN or enter VLAN Mode
2. Set or delete VLAN name
Command Explanation
VLAN Interface Mode
name <vlan-name>
no name Set or delete VLAN name.
3. Assigning Switch ports for VLAN
Command Explanation
VLAN Interface Mode
switchport interface etherent
<interface-list>
no switchport interface <interface-list>
Assign Switch ports to VLAN.
4. Set the Switch Port Type
Command Explanation
Port Mode
switchport mode {trunk | access | hybrid} Set the current port as Trunk, Access or
Hybrid port.
5. Set Trunk port
Command Explanation
Port Mode
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switchport trunk allowed vlan {WORD | all
| add WORD | except WORD | remove
WORD}
no switchport trunk allowed vlan
Set/delete VLAN allowed to be crossed
by Trunk. The “no” command restores
the default setting.
switchport trunk native vlan <vlan-id>
no switchport trunk native vlan Set/delete PVID for Trunk port.
6. Set Access port
Command Explanation
Port Mode
switchport access vlan <vlan-id>
no switchport access vlan
Add the current port to the specified
VLAN. The “no” command restores the
default setting.
7. Set Hybrid port
Command Explanation
Port Mode
switchport hybrid allowed vlan {WORD |
all | add WORD | except WORD | remove
WORD} {tag | untag}
no switchport hybrid allowed vlan
Set/delete the VLAN which is allowed by
Hybrid port with tag or untag mode.
switchport hybrid native vlan <vlan-id>
no switchport hybrid native vlan Set/delete PVID of the port.
8. Disable/Enable VLAN Ingress Rules
Command Explanation
Port Mode
vlan ingress enable
no vlan ingress enable Enable/Disable VLAN ingress rules.
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9. Configure Private VLAN
Command Explanation
VLAN Interface Mode
private-vlan {primary | isolated |
community}
no private-vlan
Configure current VLAN to Private VLAN.
The no command deletes private VLAN.
10. Set Private VLAN association
Command Explanation
VLAN Interface Mode
private-vlan association
<secondary-vlan-list>
no private-vlan association
Set/delete Private VLAN association.
11. Specify internal VLAN ID
Command Explanation
Global Mode
vlan <2-4094> internal Specify internal VLAN ID.
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20.1.3 Typical VLAN Application
Scenario:
VLAN2
VLAN100
VLAN200
PC
PC PC Workstation Workstation PC
Switch A
Trunk Link
Switch B
VLAN2
VLAN100
VLAN200
Workstation
PC
PC
PC Workstation
PC
Figure 20-2: Typical VLAN Application Topology
The existing LAN is required to be partitioned into 3 VLANs due to security and application
requirements. The three VLANs are VLAN2, VLAN100 and VLAN200. Those three VLANs
cross two different locations A and B. One switch is placed in each site, and cross-location
requirement can be met if VLAN traffic can be transferred between the two switches.
Configuration Item Configuration description
VLAN2 Site A and site B switch port 2-4.
VLAN100 Site A and site B switch port 5-7.
VLAN200 Site A and site B switch port 8-10.
Trunk port Site A and site B switch port 11.
Connect the Trunk ports of both switches for a Trunk link to convey the cross-switch VLAN
traffic; connect all network devices to the other ports of corresponding VLANs. In this example,
port 1 and port 12 are spared and can be used for management port or for other purposes.
The configuration steps are listed below:
Switch A:
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Switch(config)#vlan 2
Switch(Config-Vlan2)#switchport interface ethernet 1/2-4
Switch (Config-Vlan2)#exit
Switch (config)#vlan 100
Switch (Config-Vlan100)#switchport interface ethernet 1/5-7
Switch (Config-Vlan100)#exit
Switch (config)#vlan 200
Switch (Config-Vlan200)#switchport interface ethernet 1/8-10
Switch (Config-Vlan200)#exit
Switch (config)#interface ethernet 1/11
Switch (Config-If-Ethernet1/11)#switchport mode trunk
Switch(Config-If-Ethernet1/11)#exit
Switch(config)#
Switch B:
Switch(config)#vlan 2
Switch(Config-Vlan2)#switchport interface ethernet 1/2-4
Switch (Config-Vlan2)#exit
Switch (config)#vlan 100
Switch (Config-Vlan100)#switchport interface ethernet 1/5-7
Switch (Config-Vlan100)#exit
Switch (config)#vlan 200
Switch (Config-Vlan200)#switchport interface ethernet 1/8-10
Switch (Config-Vlan200)#exit
Switch (config)#interface ethernet 1/11
Switch (Config-If-Ethernet1/11)#switchport mode trunk
Switch (Config-If-Ethernet1/11)#exit
20.1.4 Typical Application of Hybrid Port
Scenario:
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Switch A
Switch B
internet
PC1 PC2
Figure 20-3: Typical Application of Hybrid Port
PC1 connects to the interface Ethernet 1/7 of Switch B; PC2 connects to the interface Ethernet
1/9 of Switch B; Ethernet 1/10 of Switch A connects to Ethernet 1/10 of Switch B. It is required
that PC1 and PC2 cannot mutually access due to reason of the security, but PC1 and PC2 can
access other network resources through the gateway Switch A. We can implement this status
through Hybrid port.
Configuration items are as follows:
Port Type PVID the VLANs are allowed to pass
Port 1/10 of Switch A Access 10 Allow the packets of VLAN 10 to pass
with untag method.
Port 1/10 of Switch B Hybrid 10 Allow the packets of VLAN 7, 9, 10 to
pass with untag method.
Port 1/7 of Switch B Hybrid 7 Allow the packets of VLAN 7, 10 to pass
with untag method.
Port 1/9 of Switch B Hybrid 9 Allow the packets of VLAN 9, 10 to pass
with untag method.
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The configuration steps are listed below:
Switch A:
Switch(config)#vlan 10
Switch(Config-Vlan10)#switchport interface ethernet 1/10
Switch B:
Switch(config)#vlan 7;9;10
Switch(config)#interface ethernet 1/7
Switch(Config-If-Ethernet1/7)#switchport mode hybrid
Switch(Config-If-Ethernet1/7)#switchport hybrid native vlan 7
Switch(Config-If-Ethernet1/7)#switchport hybrid allowed vlan 7;10 untag
Switch(Config-If-Ethernet1/7)#exit
Switch(Config)#interface Ethernet 1/9
Switch(Config-If-Ethernet1/9)#switchport mode hybrid
Switch(Config-If-Ethernet1/9)#switchport hybrid native vlan 9
Switch(Config-If-Ethernet1/9)#switchport hybrid allowed vlan 9;10 untag
Switch(Config-If-Ethernet1/9)#exit
Switch(Config)#interface Ethernet 1/10
Switch(Config-If-Ethernet1/10)#switchport mode hybrid
Switch(Config-If-Ethernet1/10)#switchport hybrid native vlan 10
Switch(Config-If-Ethernet1/10)#switchport hybrid allowed vlan 7;9;10 untag
Switch(Config-If-Ethernet1/10)#exit
20.2 Dot1q-tunnel Configuration
20.2.1 Introduction to Dot1q-tunnel
Dot1q-tunnel is also called Q-in-Q (802.1Q-in-802.1Q), which is an expansion of 802.1Q. Its
dominating idea is encapsulating the customer VLAN tag (CVLAN tag) to the service provider
VLAN tag (SPVLAN tag). Carrying the two VLAN tags the packet is transmitted through the
backbone network of the ISP internet, so as to provide a simple Layer 2 tunnel for the users. It
is simple and easy to manage, applicable only by static configuration, and especially adaptive
to small office network or small scale metropolitan area network using Layer 3 switch as
backbone equipment.
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SP network
P
PE1
PE2
CE1
CE2
Trunk connection
Trunk connection
Unsymmetrical connection
Unsymmetrical connection
This port on PE1 is enabled Q-in-Q and belong to VLAN3
On the customer port Trunk VLAN 200-300
On the customer port Trunk VLAN 200-300
Customer network 2
Customer network 1
This port on PE1 is enabledQ-in-Q and belong to VLAN3
Figure 20-4: Dot1q-tunnel based Internetworking mode
As shown in above, after being enabled on the user port, dot1q-tunnel assigns each user an
SPVLAN identification (SPVID). Here the identification of user is 3. The same SPVID should
be assigned for the same network user on different PEs. When packet reaches PE1 from CE1,
it carries the VLAN tag 200-300 of the user internal network. Since the dot1q-tunnel function is
enabled, the user port on PE1 will add on the packet another VLAN tag, of which the ID is the
SPVID assigned to the user. Afterwards, the packet will only be transmitted in VLAN3 when
traveling in the ISP internet network while carrying two VLAN tags (the inner tag is added when
entering PE1, and the outer is SPVID), whereas the VLAN information of the user network is
open to the provider network. When the packet reaches PE2 and before being forwarded to
CE2 from the client port on PE2, the outer VLAN tag is removed, then the packet CE2 received
is absolutely identical to the one sent by CE1. For the user, the role the operator network plays
between PE1 and PE2, is to provide a reliable Layer 2 link.
The technology of Dot1q-tuunel provides the ISP internet the ability of supporting many client
VLANs by only one VLAN of themselves. Both the ISP internet and the clients can configure
their own VLAN independently.
It is obvious that the dot1q-tunnel function has got the following characteristics:
Applicable through simple static configuration, no complex configuration or
maintenance is needed.
Operators will only have to assign one SPVID for each user, which increases the
number of concurrent supportable users while the users has got the ultimate
freedom in selecting and managing the VLAN IDs (select within 1~4094 at users’
will).
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The user network is considerably independent. When the ISP internet is upgrading
their network, the user networks do not have to change their original configuration.
Detailed description on the application and configuration of dot1q-tunnel will be provided in this
section.
20.2.2 Dot1q-tunnel Configuration
Configuration Task Sequence of Dot1q-Tunnel:
1. Configure the dot1q-tunnel function on port
2. Configure the global protocol type (TPID)
1. Configure the dot1q-tunnel function on port
2. Configure the global protocol type (TPID)
20.2.3 Typical Applications of the Dot1q-tunnel
Scenario:
Edge switches PE1 and PE2 of the ISP internet forward the VLAN200~300 data between CE1
and CE2 of the client network with VLAN3. The port1 of PE1 is connected to CE1, port10 is
connected to public network and the TPID of the connected equipment is 9100; port1 of PE2 is
connected to CE2 and port10 is connected to public network.
Configuration
Item
Configuration Explanation
VLAN3 Port1 of PE1 and PE2.
dot1q-tunnel Port1 of PE1 and PE2.
Command Explanation
Port Mode
dot1q-tunnel enable
no dot1q-tunnel enable
Enter/exit the dot1q-tunnel mode on the
port.
Command Explanation
Global Mode
dot1q-tunnel tpid
{0x8100|0x9100|0x9200|<1-65535>} Configure the global protocol type.
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tpid 9100
Configuration procedure is as follows:
PE1:
Switch(config)#vlan 3
Switch(Config-Vlan3)#switchport interface ethernet 1/1
Switch(Config-Vlan3)#exit
Switch(Config)#interface ethernet 1/1
Switch(Config-Ethernet1/1)# dot1q-tunnel enable
Switch(Config-Ethernet1/1)# exit
Switch(Config)#interface ethernet 1/10
Switch(Config-Ethernet1/10)#switchport mode trunk
Switch(Config-Ethernet1/10)#exit
Switch(config)#dot1q-tunnel tpid 0x9100
Switch(Config)#
PE2:
Switch(config)#vlan 3
Switch(Config-Vlan3)#switchport interface ethernet 1/1
Switch(Config-Vlan3)#exit
Switch(Config)#interface ethernet 1/1
Switch(Config-Ethernet1/1)# dot1q-tunnel enable
Switch(Config-Ethernet1/1)# exit
Switch(Config)#interface ethernet 1/10
Switch(Config-Ethernet1/10)#switchport mode trunk
Switch(Config-Ethernet1/10)#exit
Switch(config)#dot1q-tunnel tpid 0x9100
Switch(Config)#
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20.2.4 Dot1q-tunnel Troubleshooting
Enabling dot1q-tunnel on Trunk port will make the tag of the data packet
unpredictable which is not required in the application. So it is not recommended to
enable dot1q-tunnel on Trunk port.
Enabled with STP/MSTP is not supported.
20.3 Selective Q-in-Q Configuration
20.3.1 Introduction to Selective Q-in-Q
Selective Q-in-Q is an enhanced application for dot1q tunnel function. It is able to tag packets
(they are received by the same port) with different outer VLAN tags based on different inner
VLAN tags according to user’s requirement, so it is able to implement packets of different
types assigned to different VLANs by selecting different transmission paths.
20.3.2 Selective Q-in-Q Configuration
Selective Q-in-Q Configuration Task List:
1. Configure the port mapping relation between the inner tag and the outer tag
2. Configure selective Q-in-Q of port
1. Configure the port mapping relation between the inner tag and the outer tag
Command Explanation
Port Mode
dot1q-tunnel selective s-vlan <s-vid>
c-vlan <c-vid-list>
no dot1q-tunnel selective s-vlan <s-vid>
c-vlan <c-vid-list>
Configure/delete the port mapping
relation of the inner tag and the outer tag
for selective Q-in-Q.
2. Configure selective Q-in-Q of port
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Command Explanation
Port Mode
dot1q-tunnel selective enable
no dot1q-tunnel selective enable
Enable/disable selective Q-in-Q of the
port.
20.3.3 Typical Applications of Selective Q-in-Q
Figure 20-5: Selective QinQ application
1. Ethernet1/1 of Switch A provides public network access for PC users and Ethernet 1/2 of
Switch A provides public network access for IP phone users. PC users belong to VLAN 100
through VLAN 200, and IP phone users belong to VLAN 201 through VLAN 300. Ethernet 1/9
of Switch A is connected to the public network.
2. Ethernet1/1 and Ethernet1/2 of Switch B provide network access for PC users belonging to
VLAN 100 through VLAN 200 and IP phone users belonging to VLAN 201 through VLAN 300
respectively. Ethernet 1/9 is connected to the public network.
3. The public network permits packets of VLAN 1000 and VLAN 2000 to pass.
4. Enable the selective Q-in-Q on Ethernet1/1 and Ethernet1/2 ports of Switch A and Switch B
respectively. Packets of VLAN 100 through VLAN 200 are tagged with the tag of VLAN 1000
as the outer VLAN tag on Ethernet1/1, and packets of VLAN 201 through VLAN 300 are
tagged with the tag of VLAN 2000 as the outer VLAN tag on Ethernet1/2.
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Steps of configuration:
# Create VLAN 1000 and VLAN 2000 on SwitchA.
switch(config)#vlan 1000;2000
# Configure Ethernet1/1 as a hybrid port and configure it to remove VLAN tags when
forwarding packets of VLAN 1000.
switch(config-if-ethernet1/1)#switchport hybrid allowed vlan 1000 untag
# Configure the mapping rules for selective Q-in-Q on Ehernet1/1 to insert VLAN 1000 tag as
the outer VLAN tag in packets with the tags of VLAN 100 through VLAN 200.
switch(config-if-ethernet1/1)#dot1q-tunnel selective s-vlan 1000 c-vlan 100-200
# Enable selective Q-in-Q on Ethernet1/1.
switch(config-if-ethernet1/1)#dot1q-tunnel selective enable
# Configure Ethernet 1/2 as a hybrid port and configure it to remove VLAN tags when
forwarding packets of VLAN 2000.
switch(config-if-ethernet1/2)#switchport mode hybrid
switch(config-if-ethernet1/2)#switchport hybrid allowed vlan 2000 untag
# Configure mapping rules for selective Q-in-Q on Ehernet1/2 to insert VLAN 2000 tag as the
outer VLAN tag in packets with the tags of VLAN 201 through VLAN 300.
switch(config-if-ethernet1/2)#dot1q-tunnel selective s-vlan 2000 c-vlan 201-300
# Enable selective Q-in-Q on Ethernet 1/2.
switch(config-if-ethernet1/2)#dot1q-tunnel selective enable
# Configure uplink port Ethernet 1/9 as a hybrid port and configure it to save VLAN tags when
forwarding packets of VLAN 1000 and VLAN 2000.
switch(config-if-ethernet1/2)#interface ethernet 1/9
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switch(config-if-ethernet1/9)#switchport mode hybrid
switch(config-if-ethernet1/9)#switchport hybrid allowed vlan 1000;2000 tag
After the above configuration, packets of VLAN 100 through VLAN 200 from Ethernet1/1 are
automatically tagged with the tag of VLAN 1000 as the outer VLAN tag, and packets of VLAN
201 through VLAN 300 from Ethernet1/2 are automatically tagged with the tag of VLAN 2000
as the outer VLAN tag on SwitchA.
The configuration on Switch B is similar to that on Switch A and the configuration is as follows:
switch(config)#vlan 1000;2000
switch(config)#interface ethernet 1/1
switch(config-if-ethernet1/1)#switchport mode hybrid
switch(config-if-ethernet1/1)#switchport hybrid allowed vlan 1000 untag
switch(config-if-ethernet1/1)#dot1q-tunnel selective s-vlan 1000 c-vlan 100-200
switch(config-if-ethernet1/1)#dot1q-tunnel selective enable
switch(config-if-ethernet1/1)#interface ethernet 1/2
switch(config-if-ethernet1/2)#switchport hybrid allowed vlan 2000 untag
switch(config-if-ethernet1/2)#dot1q-tunnel selective s-vlan 2000 c-vlan 201-300
switch(config-if-ethernet1/2)#dot1q-tunnel selective enable
switch(config-if-ethernet1/9)#switchport mode hybrid
switch(config-if-ethernet1/9)#switchport hybrid allowed vlan 1000;2000 tag
20.3.4 Selective Q-in-Q Troubleshooting
Selective Q-in-Q and dot1q-tunnel functions should not be configured synchronously
for a port.
20.4 VLAN Translation Configuration
20.4.1 Introduction to VLAN Translation
VLAN translation, as one can tell from the name, which translates the original VLAN ID to new
VLAN ID according to the user requirements so to exchange data across different VLANs.
VLAN translation supports ingress translation, and switch over the VLAN ID at the ingress.
Application and configuration of VLAN translation will be explained in details in this section.
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20.4.2 VLAN Translation Configuration
Configuration task sequence of VLAN translation:
1. Configure the VLAN translation function on the port
2. Configure the VLAN translation relations on the port
3. Configure whether the packet is dropped when VLAN translation fails
4. Show the related configuration of VLAN translation
1. Configure the VLAN Translation of the port
Command Explanation
Port Mode
vlan-translation enable
no vlan-translation enable
Enter/exit the port VLAN translation
mode.
2. Configure the VLAN-translation relation of the port
Command Explanation
Global/Port Mode
vlan-translation <old-vlan-id> to
<new-vlan-id> in
no vlan-translation old-vlan-id in
Add/delete a VLAN translation relation.
3. Configure whether the packet is dropped when VLAN translation fails
Command Explanation
Port Mode
vlan-translation miss drop {in | out | both}
no vlan-translation miss drop {in | out |
both}
Configure the VLAN translation packet
dropped on port if there is any failure.
4. Show the related configuration of VLAN translation
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Command Explanation
Admin Mode
show vlan-translation Show the related configuration of VLAN
translation.
20.4.3 Typical Application of VLAN Translation
Scenario:
Edge switches PE1 and PE2 of the ISP internet support the VLAN20 data task between CE1
and CE2 of the client network with VLAN3. The port1/1 of PE1 is connected to CE1; port1/10 is
connected to public network; port1/1 of PE2 is connected to CE2; port1/10 is connected to
public network.
SP networks
P
PE1
PE2
CE1
CE2
Trunk connection
Trunk connection
Trunk connection
Trunk connection
The ingress of the port translates VLAN20 to VLAN3, the egress translates VLAN3 to VLAN20 on PE
On the customer port Trunk VLAN 20
On the customer port Trunk VLAN 200-300
Customer networks2
Customer networks1
The ingress of the porttranslates VLAN20 to VLAN3,the egress translates VLAN3 toVLAN20 on PE
Figure 20-6: VLAN translation topology mode
Configuration
Item
Configuration Explanation
VLAN translation Port1/1 of PE1 and PE2.
Trunk port Port1/1 and Port1/10 of PE1 and PE2.
Configuration procedure is as follows:
PE1、PE2:
switch(Config)#interface ethernet 1/1
switch(Config-Ethernet1/1)#switchport mode trunk
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switch(Config-Ethernet1/1)# vlan-translation enable
switch(Config-Ethernet1/1)# vlan-translation 20 to 3 in
switch(Config-Ethernet1/1)# vlan-translation 3 to 20 out
switch(Config-Ethernet1/1)# exit
switch(Config)#interface ethernet 1/10
switch(Config-Ethernet1/10)#switchport mode trunk
switch(Config-Ethernet1/10)#exit
switch(Config)#
Note: This switch only supports the in direction.
20.4.4 VLAN Translation Troubleshooting
Normally the VLAN Translation is applied on trunk ports. Normally before using the VLAN
Translation, the dot1q-tunnel function needs to be enabled first to adapt double tag data
packet processes VLAN-translation. When configuring VLAN translation of the egress, make
sure native VLAN of the port is not identical with vid of the packet. Otherwise, the tag of the
packet will be stripped in advance and the transform of vid cannot be completed.
QoS only matches VLAN-id that the packet is translated when VLAN translation and QoS are
configured at the same time.
20.5 Multi-to-One VLAN Translation Configuration
20.5.1 Introduction to Multi-to-One VLAN Translation
Multi-to-One VLAN translation translates the original VLAN ID into the new VLAN ID according
to user’s requirement on uplink traffic, and restores the original VLAN ID on downlink traffic.
Application and configuration of Multi-to-One VLAN translation will be explained in details in
this section.
20.5.2 Multi-to-One VLAN Translation Configuration
Multi-to-One VLAN translation configuration task list:
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1. Configure Multi-to-One VLAN translation on the port
2. Show the related configuration of Multi-to-One VLAN translation
1. Configure Multi-to-One VLAN translation on the port
Command Explanation
Port Mode
vlan-translation n-to-1 <WORD> to
<new-vlan-id>
no vlan-translation n-to-1 <WORD>
Configure/delete Multi-to-One VLAN
translation.
2. Show the related configuration of Multi-to-One VLAN translation
Command Explanation
Admin Mode
show vlan-translation n-to-1 Show the related configuration of
Multi-to-One VLAN translation.
20.5.3 Typical Application of Multi-to-One VLAN
Translation
Scenario:
UserA, userB and userC belong to VLAN1, VLAN2, VLAN3, respectively. Before entering the
network layer, data traffic of userA, userB and userC is translated into VLAN 100 by
Ethernet1/1 of edge switch1. Contrarily, data traffic of userA, userB and userC will be
translated into VLAN1, VLAN2, VLAN3 by Ethernet1/1 of edge switch1 from network layer
respectively. In the same way, it implements multi-to-one translation for userD, userE and
userF on Ethernet1/1 of edge switch2.
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Figure 20-7: VLAN translation typical application
Configuration Item Configuration Explanation
VLAN Switch1、Switch2
Trunk Port Downlink port 1/1 and uplink port 1/5 of Switch1 and Switch 2
Multi-to-One
VLAN-translation
Downlink port 1/1 of Switch1 and Switch2
Configuration procedure is as follows:
Switch1、Switch2:
switch(Config)# vlan 1-3;100
switch(Config-Ethernet1/1)#switchport mode trunk
switch(Config-Ethernet1/1)# vlan-translation n-to-1 1-3 to 100
switch(Config)#interface ethernet 1/5
switch(Config-Ethernet1/5)#switchport mode trunk
switch(Config-Ethernet1/5)#exit
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20.5.4 Multi-to-One VLAN Translation Troubleshooting
Do not be used with Dot1q-tunnel at the same time.
Do not be used with VLAN translation at the same time.
The same MAC address should not exist in the original and the translated VLAN.
Check whether the hardware resource of the chip is able to ensure all clients to work
normally.
Limiting learning of MAC address may affect Multi-to-One VLAN Translation.
Multi-to-One VLAN Translation should be enabled after MAC learning.
20.6 Dynamic VLAN Configuration
20.6.1 Introduction to Dynamic VLAN
The dynamic VLAN is named corresponding to the static VLAN (namely the port based VLAN).
Dynamic VLAN supported by the switch includes MAC-based VLAN, IP-subnet-based VLAN
and Protocol-based VLAN. Detailed description is as follows:
The MAC-based VLAN division is based on the MAC address of each host, namely every host
with a MAC address will be assigned to certain VLAN. By the means, the network user will
maintain his membership in his belonging VLAN when moving from a physical location to
another. We can see the greatest advantage of this VLAN division is that the VLAN does not
have to be re-configured when the user physical location changes, meaning shifting from one
switch to another, which is because it is user based, not switch port based.
The IP subnet based VLAN is divided according to the source IP address and its subnet mask
of every host. It assigns corresponding VLAN ID to the data packet according to the subnet
segment, leading the data packet to specified VLAN. Its advantage is the same as that of the
MAC-based VLAN; the user does not have to change configuration when relocated.
The VLAN is divided by the network layer protocol, assigning a different protocol to different
VLANs. This is very attractive to the network administrators who wish to organize the user by
applications and services. Moreover the user can move freely within the network while
maintaining his membership. Advantage of this method enables user to change physical
position without changing their VLAN residing configuration, while the VLAN can be divided by
types of protocols which is important to the network administrators. Further, this method has
no need of added frame label to identify the VLAN, which reduces the network traffic.
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Note: Dynamic VLAN needs to associate with Hybrid attribute of the ports to work, so the ports
that may be added to a dynamic VLAN must be configured as Hybrid port.
20.6.2 Dynamic VLAN Configuration
Dynamic VLAN Configuration Task Sequence:
1. Configure the MAC-based VLAN function on the port
2. Set the VLAN to MAC VLAN
3. Configure the correspondence between the MAC address and the VLAN
4. Configure the IP-subnet-based VLAN function on the port
5. Configure the correspondence between the IP subnet and the VLAN
6. Configure the correspondence between the Protocols and the VLAN
7. Adjust the priority of the dynamic VLAN
1. Configure the MAC-based VLAN function on the port
Command Explanation
Port Mode
switchport mac-vlan enable
no switchport mac-vlan enable
Enable/disable the MAC-based VLAN
function on the port.
2. Set the VLAN to MAC VLAN
Command Explanation
Global Mode
mac-vlan vlan <vlan-id>
no mac-vlan
Configure the specified VLAN to MAC
VLAN; the “no mac-vlan” command
cancels the MAC VLAN configuration of
this VLAN.
3. Configure the correspondence between the MAC address and the VLAN
Command Explanation
Global Mode
mac-vlan mac <mac-addrss> vlan Add/delete the correspondence between
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<vlan-id> priority <priority-id>
no mac-vlan {mac <mac-addrss>|all}
the MAC address and the VLAN, namely
specified MAC address join/leave
specified VLAN.
4. Configure the IP-subnet-based VLAN function on the port
Command Explanation
Port Mode
switchport subnet-vlan enable
no switchport subnet-vlan enable
Enable/disable the port IP-subnet-base
VLAN function on the port.
5. Configure the correspondence between the IP subnet and the VLAN
Command Explanation
Global Mode
subnet-vlan ip-address <ipv4-addrss>
mask <subnet-mask> vlan <vlan-id>
priority <priority-id>
no subnet-vlan {ip-address <ipv4-addrss>
mask <subnet-mask>|all}
Add/delete the correspondence between
the IP subnet and the VLAN, namely
specified IP subnet joins/leaves specified
VLAN.
6. Configure the correspondence between the Protocols and the VLAN
Command Explanation
Global Mode
protocol-vlan mode {ethernetii etype
<etype-id>|llc {dsap <dsap-id> ssap
<ssap-id>}|snap etype <etype-id>} vlan
<vlan-id> priority <priority-id>
no protocol-vlan {mode {ethernetii etype
<etype-id>|llc {dsap <dsap-id> ssap
<ssap-id>}|snap etype <etype-id>}|all}
Add/delete the correspondence between
the Protocols and the VLAN, namely
specified protocol joins/leaves specified
VLAN.
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7. Adjust the priority of the dynamic VLAN
20.6.3 Typical Application of the Dynamic VLAN
Scenario:
In the office network Department A belongs to VLAN100. Several members of this department
often have the need to move within the whole office network. It is also required to ensure the
resource for other members of the department to access VLAN 100. Assume one of the
members is M, the MAC address of his PC is 00-30-4f-11-22-33, when M moves to VLAN200
or VLAN300, the port connecting M is configured as Hybrid mode and belongs to VLAN100
with untag mode. In this way, the data of VLAN100 will be forwarded to the port connecting M,
and implement the communication requirement in VLAN100.
Figure 20-8: Typical topology application of dynamic VLAN
Configuration
Items
Configuration Explanation
MAC-based VLAN Global configuration on Switch A, Switch B, Switch C.
Command Explanation
Global Mode
dynamic-vlan mac-vlan prefer
dynamic-vlan subnet-vlan prefer
Configure the priority of the dynamic
VLAN.
Switch A Switch B Switch C
VLAN100
VLAN200
VLAN300
M
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For example, M at E1/1 of Switch A, then the configuration procedures are as follows:
Switch A, Switch B, Switch C:
SwitchA (Config)#mac-vlan mac 00-03 -0f-11-22-33 vlan 100 priority 0
SwitchA (Config)#interface ethernet 1/1
SwitchA (Config-Ethernet1/1)# swportport mode hybrid
SwitchA (Config-Ethernet1/1)# swportport hybrid allowed vlan 100 untagged
SwitchB (Config)#mac-vlan mac 00-30-4f-11-22-33 vlan 100 priority 0
SwitchB (Config)#exit
SwitchB#
SwitchC (Config)#mac-vlan mac 00-30-4f-11-22-33 vlan 100 priority 0
SwitchC (Config)#exit
SwitchC#
20.6.4 Dynamic VLAN Troubleshooting
On the switch configured with dynamic VLAN, if the two connected equipment (e.g.
PC) both belongs to the same dynamic VLAN, first communication between the two
equipment may not go through. The solution will be letting the two equipment
positively send data packet to the switch (such as ping), to let the switch learn their
source MAC, then the two equipment will be able to communicate freely within the
dynamic VLAN.
Ping 192.168.1.200 Ping 192.168.1.100
192.168.1.100/24 192.168.1.200/24
Dynamic VLAN
Figure 20-9: Dynamic VLAN Troubleshooting
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20.7 GVRP Configuration
20.7.1 Introduction to GVRP
GVRP, i.e. GARP VLAN Registration Protocol, is an application of GARP (Generic Attribute
Registration Protocol). GARP is mainly used to establish an attribute transmission mechanism
to transmit attributes, so as to ensure protocol entities registering and deregistering the
attribute. According to different transmission attributes, GARP can be divided into many
application protocols, such as GMRP and GVRP. Therefore, GVRP is a protocol which
transmits VLAN attributes to the whole Layer 2 network through GARP Protocol.
Figure 20-10: a typical application scene
A and G switches are not directly connected in Layer 2 network; BCDEF are intermediate
switches connecting A and G. Switch A and G configure VLAN100-1000 manually while
BCDEF switches do not. When GVRP is not enabled, A and G cannot communicate with each
other, because intermediate switches without relevant VLANs. However, after GVRP is
enabled on all switches, its VLAN attribute transmission mechanism enables the intermediate
switches registering the VLANs dynamically, and the VLAN in VLAN100-1000 of A and G can
communicate with each other. The VLANs dynamically registered by intermediate switches will
be deregistered when deregistering VLAN100-1000 of A and G switches manually. So the
same VLAN of two unadjacent switches can communicate mutually through GVRP protocol
instead of configuring each intermediate switch manually for achieving the purpose of
simplifying VLAN configuration.
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20.7.2 GVRP Configuration Task List
GVRP configuration task list:
1. Configure GVRP timer
2. Configure port type
3. Enable GVRP function
1. Configure GVRP timer
Command Explanation
Global Mode
garp timer join <200-500>
garp timer leave <500-1200>
garp timer leaveall <5000-60000>
no garp timer (join | leave | leaveAll)
Configure leaveall, join and leave
timer for GVRP.
2. Configure port type
Command Explanation
Port Mode
gvrp
no gvrp
Enable/ disable GVRP function of
port.
3. Enable GVRP function
Command Explanation
Global Mode
gvrp
no gvrp
Enable/ disable the global GVRP
function of port.
20.7.3 Example of GVRP
GVRP application:
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PC
PC
Switch A
Switch B
Switch C
Figure 20-11: Typical GVRP Application Topology
To enable dynamic VLAN information register and update among switches, GVRP protocol is
to be configured in the switch. Configure GVRP in Switch A, B and C, enable Switch B to learn
VLAN100 dynamically so that two workstations connected to VLAN100 in Switch A and C can
communicate with each other through Switch B without static VLAN100 entries.
Configuration
Item
Configuration description
VLAN100 Port 2-6 of Switch A and C.
Trunk port Port 11 of Switch A and C, Port 10, 11 of Switch B.
Global GVRP Switch A, B, C.
Port GVRP Port 11 of Switch A and C, Port 10, 11 of Switch B.
Connect two workstations to the VLAN100 ports in switch A and B, connect port 11 of Switch A
to port 10 of Switch B, and port 11 of Switch B to port 11 of Switch C.
The configuration steps are listed below:
Switch A:
Switch(config)# gvrp
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Switch(config)#vlan 100
Switch(Config-Vlan100)#switchport interface ethernet 1/2-6
Switch(Config-Vlan100)#exit
Switch(config)#interface ethernet 1/11
Switch(Config-If-Ethernet1/11)#switchport mode trunk
Switch(Config-If-Ethernet1/11)# gvrp
Switch(Config-If-Ethernet1/11)#exit
Switch B:
Switch(config)#gvrp
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#switchport mode trunk
Switch(Config-If-Ethernet1/10)# gvrp
Switch(Config-If-Ethernet1/10)#exit
Switch(config)#interface ethernet 1/11
Switch(Config-If-Ethernet1/11)#switchport mode trunk
Switch(Config-If-Ethernet1/11)# gvrp
Switch(Config-If-Ethernet1/11)#exit
Switch C:
Switch(config)# gvrp
Switch(config)#vlan 100
Switch(Config-Vlan100)#switchport interface ethernet 1/2-6
Switch(Config-Vlan100)#exit
Switch(config)#interface ethernet 1/11
Switch(Config-If-Ethernet1/11)#switchport mode trunk
Switch(Config-If-Ethernet1/11)# gvrp
Switch(Config-If-Ethernet1/11)#exit
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20.7.4 GVRP Troubleshooting
The GARP counter setting for Trunk ports in both ends of Trunk link must be the same,
otherwise, GVRP will not work normally. It is recommended to avoid enabling GVRP and
RSTP at the same time in switch. If GVRP needs to be enabled, RSTP function for the ports
must be disabled first.
20.8 Voice VLAN Configuration
20.8.1 Introduction to Voice VLAN
Voice VLAN is specially configured for the user voice data traffic. By setting a Voice VLAN and
adding the ports of the connected voice equipment to the Voice VLAN, the user will be able to
configure QoS (Quality of service) service for voice data, and improve the voice data traffic
transmission priority to ensure the calling quality.
The switch can judge if the data traffic is the voice data traffic from specified equipment
according to the source MAC address field of the data packet entering the port. The packet
with the source MAC address complying with the system defined voice equipment OUI
(Organizationally Unique Identifier) will be considered the voice data traffic and transmitted to
the Voice VLAN.
The configuration is based on MAC address, acquiring a mechanism in which every voice
equipment transmitting information through the network has got its unique MAC address.
VLAN will trace the address that belongs to specified MAC. By this means, VLAN allows the
voice equipment to always belong to Voice VLAN when relocated physically. The greatest
advantage of the VLAN is the equipment that can be automatically placed into Voice VLAN
according to its voice traffic which will be transmitted at specified priority. Meanwhile, when
voice equipment is physically relocated, it still belongs to the Voice VLAN without any further
configuration modification, which is because it is based on voice equipment other than switch
port.
Note: Voice VLAN needs to associate with Hybrid attribute of the ports to work, so the ports
that may be added to Voice VLAN must be configured as Hybrid port.
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20.8.2 Voice VLAN Configuration
Voice VLAN Configuration Task Sequence:
1. Set the VLAN to Voice VLAN
2. Add a voice equipment to Voice VLAN
3. Enable the Voice VLAN on the port
1. Configure the VLAN to Voice VLAN
Command Explanation
Global Mode
voice-vlan vlan <vlan-id>
no voice-vlan Set/cancel the VLAN as a Voice VLAN
2. Add a Voice equipment to a Voice VLAN
Command Explanation
Global Mode
voice-vlan mac <mac-address> mask
<mac-mask> priority <priority-id> [name
<voice-name>]
no voice-vlan {mac <mac-address> mask
<mac-mask>|name <voice-name> |all}
Specify certain voice equipment
join/leave the Voice VLAN
3. Enable the Voice VLAN of the port
Command Explanation
Port Mode
switchport voice-vlan enable
no switchport voice-vlan enable
Enable/disable the Voice VLAN function
on the port
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20.8.3 Typical Applications of the Voice VLAN
Scenario:
A company realizes voice communication through configuring Voice VLAN. IP-phone1 and
IP-phone2 can be connected to any port of the switch, namely normal communication and
interconnected with other switches through the uplink port. IP-phone1 MAC address is
00-30-4f-11-22-33, connect port 1/1 of the switch, IP-phone2 MAC address is
00-30-4f-11-22-55, connect port 1/2 of the switch.
Switch
IP-phone1 IP-phone2
Figure 20-12: VLAN typical apply topology Figure
uration Configuration Explanation
Config
items
Voice VLAN Global configuration on the Switch.
Configuration procedure:
witch 1:
-11-22-55 mask 255 priority 5 name company
hport mode trunk
S
Switch(config)#vlan 100
Switch(Config-Vlan100)#exit
Switch(config)#voice-vlan vlan 100
Switch(config)#voice-vlan mac 00-30-4f-11-22-33 mask 255 priority 5 name company
Switch(config)#voice-vlan mac 00-30-4f
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#switc
Switch(Config-If-Ethernet1/10)#exit
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switch(Config)#interface ethernet 1/1
switch(Config-If-Ethernet1/1)#switchport mode hybrid
switch(Config-If-Ethernet1/1)#switchport hybrid allowed vlan 100 untag
ort hybrid allowed vlan 100 untag
witch(Config-If-Ethernet1/2)#exit
20.8.4 Voice VLAN Troubleshooting
024 sets of voice equipment; the exceeded number of equipment will not be
peration, please check if the Voice VLAN
function has been disabled on the port.
switch(Config-If-Ethernet1/1)#exit
switch(Config)#interface ethernet 1/2
switch(Config-If-Ethernet1/2)#switchport mode hybrid
switch(Config-If-Ethernet1/2)#switchp
s
Voice VLAN cannot be applied concurrently with MAC-base VLAN. The Voice VLAN supports
maximum 1
supported.
The Voice VLAN on the port is enabled by default. If the configured data can no
longer enter the Voice VLAN during o
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Chapter 21 MAC Table Configuration
21.1 Introduction to MAC Table
MAC table is a table identifies the mapping relationship between destination MAC addresses
and switch ports. MAC addresses can be categorized as static MAC addresses and dynamic
MAC addresses. Static MAC addresses are manually configured by the user, have the highest
priority and are permanently effective (will not be overwritten by dynamic MAC addresses);
dynamic MAC addresses are entries learnt by the switch in data frame forwarding, and is
effective for a limited period. When the switch receives a data frame to be forwarded, it stores
the source MAC address of the data frame and creates a mapping to the destination port.
Then the MAC table is queried for the destination MAC address, if hit, the data frame is
forwarded in the associated port; otherwise, the switch forwards the data frame to its
broadcast domain. If a dynamic MAC address is not learnt from the data frames to be
forwarded for a long time, the entry will be deleted from the switch MAC table.
There are two MAC table operations:
1. Obtain a MAC address.
2. Forward or filter data frame according to the MAC table.
21.1.1 Obtaining MAC Table
The MAC table can be built up statically and dynamically. Static configuration is to set up a
mapping between the MAC addresses and the ports; dynamic learning is the process in which
the switch learns the mapping between MAC addresses and ports, and updates the MAC table
regularly. In this section, we will focus on the dynamic learning process of MAC table.
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Figure 21-1: MAC Table dynamic learning
The topology of the figure above: 4 PCs connected to switch, where PC1 and PC2 belongs to
the same physical segment (same collision domain), the physical segment connects to port
1/5 of switch; PC3 and PC4 belongs to the same physical segment that connects to port 1/12
of switch.
The initial MAC table contains no address mapping entries. Take the communication of PC1
and PC3 for an example. The MAC address learning process is as follows:
1. When PC1 sends message to PC3, the switch receives the source MAC address
00-01-11-11-11-11 from this message. The mapping entry of 00-01-11-11-11-11 and port
1/5 are added to the switch MAC table.
2. At the same time, the switch learns the message which is destined to 00-01-33-33-33-33,
as the MAC table contains only a mapping entry of MAC address 00-01-11-11-11-11 and
port1/5, and no port mapping for 00-01-33-33-33-33 is present. The switch broadcasts this
message to all the ports in the switch (assuming all ports belong to the default VLAN1).
3. PC3 and PC4 on port 1/12 receive the message sent by PC1, but PC4 will not reply, as the
destination MAC address is 00-01-33-33-33-33, only PC3 will reply to PC1. When port
1/12 receives the message sent by PC3, a mapping entry for MAC address
00-01-33-33-33-33 and port 1/12 is added to the MAC table.
4. Now the MAC table has two dynamic entries, MAC address 00-01-11-11-11-11 - port 1/5
and 00-01-33-33-33-33 -port1/12.
5. After the communication between PC1 and PC3, the switch does not receive any message
sent from PC1 and PC3. And the MAC address mapping entries in the MAC table are
deleted in 300 to 2*300 seconds (ie, in single to double aging time). The 300 seconds here
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is the default aging time for MAC address entry in switch. Aging time can be modified in
switch.
21.1.2 Forward or Filter
The switch will forward or filter received data frames according to the MAC table. Take the
above figure for an example. Assuming switch has learned the MAC address of PC1 and PC3,
and the user manually configures the mapping relationship for PC2 and PC4 to ports. The
MAC table of switch will be:
MAC Address Port number Entry added by
00-01-11-11-11-11 1/5 Dynamic learning
00-01-22-22-22-22 1/5 Static configuration
00-01-33-33-33-33 1/12 Dynamic learning
00-01-44-44-44-44 1/12 Static configuration
1． Forward data according to the MAC table
If PC1 sends a message to PC3, the switch will forward the data received on port 1/5 from
port1/12.
2． Filter data according to the MAC table
If PC1 sends a message to PC2, the switch, on checking the MAC table, will find PC2 and PC1,
which are in the same physical segment and filter the message (i.e. drop this message).
Three types of frames can be forwarded by the switch:
Broadcast frame
Multicast frame
Unicast frame
The following describes how the switch deals with all the three types of frames:
1． Broadcast frame: The switch can segregate collision domains but not broadcast
domains. If no VLAN is set, all devices connected to the switch are in the same
broadcast domain. When the switch receives a broadcast frame, it forwards the frame
in all ports. When VLANs are configured in the switch, the MAC table will be adapted
accordingly to add VLAN information. In this case, the switch will not forward the
received broadcast frames in all ports, but forward the frames in all ports in the same
VLAN.
2． Multicast frame: For the unknown multicast, the switch will broadcast it in the same
VLAN, but the switch only forwards the multicast frames to the multicast group’s port
if IGMP Snooping function or the static multicast group has been configured.
3． Unicast frame: When no VLAN is configured, if the destination MAC addresses are in
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the switch MAC table, the switch will directly forward the frames to the associated
ports; when the destination MAC address in a unicast frame is not found in the MAC
table, the switch will broadcast the unicast frame. When VLANs are configured, the
switch will forward unicast frame within the same VLAN. If the destination MAC
address is found in the MAC table but belonging to different VLANs, the switch can
only broadcast the unicast frame in the VLAN it belongs to.
21.2 Mac Address Table Configuration Task List
1. Configure the MAC address aging-time
2. Configure static MAC forwarding or filter entry
3. Clear dynamic address table
4. Configure MAC learning through CPU control
1. Configure the MAC aging-time
Command Explanation
Global Mode
mac-address-table aging-time
<0|aging-time>
no mac-address-table aging-time
Configure the MAC address aging-time.
2. Configure static MAC forwarding or filter entry
Command Explanation
Global Mode
mac-address-table {static | static-multicast
| blackhole} address <mac-addr> vlan
<vlan-id > [interface ethernet
<interface-name>] |
[source|destination|both]
no mac-address-table {static |
static-multicast | blackhole } [address
<mac-addr>] [vlan <vlan-id>] [interface
ethernet <interface-name>]
Configure static MAC entries, static
multicast MAC entries, filter address
entries.
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3. Clear dynamic address table
Command Explanation
Admin Mode
clear mac-address-table dynamic [address
<mac-addr>] [vlan <vlan-id>] [interface
[ethernet | portchannel] <interface-name>]
Clear the dynamic address table.
4. Configure MAC learning through CPU control
Command Explanation
Global Mode
mac-address-learning cpu-control
no mac-address-learning cpu-control
Enable MAC learning through CPU
control, the no command restores that
the chip automatically learn MAC
address.
show collision-mac-address-table Show the hash collision mac table.
Admin Mode
clear collision-mac-address-table Clear the hash collision mac table.
21.3 Typical Configuration Examples
Figure 22-3: MAC Table typical configuration example
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Scenario:
Four PCs as shown in the above figure connect to port 1/5, 1/7, 1/9, 1/11 of switch; all the four
PCs belong to the default VLAN1. As required by the network environment, dynamic learning
is enabled. PC1 holds sensitive data and cannot be accessed by any other PC that is in
another physical segment; PC2 and PC3 have static mapping set to port 1/7 and port 1/9,
respectively.
The configuration steps are listed below:
1. Set the MAC address 00-01-11-11-11-11 of PC1 as a filter address.
Switch(config)#mac-address-table static 00-01-11-11-11-11 discard vlan 1.
2.Set the static mapping relationship for PC2 and PC3 to port 1/7 and port 1/9, respectively.
Switch(config)#mac-address-table static address 00-01-22-22-22-22 vlan 1 interface
ethernet 1/7
Switch(config)#mac-address-table static address 00-01-33-33-33-33 vlan 1 interface
ethernet 1/9
21.4 MAC Table Troubleshooting
Using the show mac-address-table command, a port is found to be failed to learn the MAC of a
device connected to it. Possible reasons:
The connected cable is broken.
Spanning Tree is enabled and the port is in “discarding” status; or the device is just
connected to the port and Spanning Tree is still under calculation, wait until the
Spanning Tree calculation finishes, and the port will learn the MAC address.
If not the problems mentioned above, please check the switch port and contact
technical support for solution.
21.5 MAC Address Function Extension
21.5.1 MAC Address Binding
21.5.1.1 Introduction to MAC Address Binding
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Most switches support MAC address learning; each port can dynamically learn several MAC
addresses, so that forwarding data streams between known MAC addresses within the ports
can be achieved. If an MAC address is aged, the packet destined for that entry will be
broadcasted. In other words, an MAC address learned in a port will be used for forwarding in
that port, if the connection is changed to another port, the switch will learn the MAC address
again to forward data in the new port.
However, in some cases, security or management policy may require MAC addresses to be
bound with the ports, only data stream from the binding MAC are allowed to be forwarded in
the ports. That is to say, after a MAC address is bound to a port, only the data stream destined
for that MAC address can flow in from the binding port, data stream destined for the other MAC
addresses that not bound to the port will not be allowed to pass through the port.
21.5.1.2 MAC Address Binding Configuration Task List
1. Enable MAC address binding function for the ports
2. Lock the MAC addresses for a port
3. MAC address binding property configuration
1. Enable MAC address binding function for the ports
Command Explanation
Port Mode
switchport port-security
no switchport port-security
Enable MAC address binding function for
the port and lock the port. When a port is
locked, the MAC address learning function
for the port will be disabled: the “no
switchport port-security” command
disables the MAC address binding function
for the port, and restores the MAC address
learning function for the port.
2. Lock the MAC addresses for a port
Command Explanation
Port Mode
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switchport port-security aging {static |
time <value> | type {absolute |
inactivity}}
no switchport port-security violation
aging {static | time | type}
Enable the aging entries of port-security,
and specify the aging time and type on the
interface.
switchport port-security mac-address
<mac-address> [vlan <vlan-id>]
no switchport port-security
mac-address <mac-address> [vlan
<vlan-id>]
Configure the static secure MAC on the
interface, the no command cancels the
configuration.
Admin Mode
clear port-security dynamic [address
<mac-addr> | interface <interface-id>]
Clear dynamic MAC addresses learned by
the specified port.
3. MAC address binding property configuration
Command Explanation
Port Mode
switchport port-security maximum
<value> [vlan <vlan-list>]
no switchport port-security maximum
<value> [vlan <vlan-list>]
Configure the maximum number of the
secure MAC allowed by the interface, if
specifying VLAN parameter, it means the
maximum number in the configured
VLANs. The no command cancels the
maximum number of the secure MAC
configured by the interface.
switchport port-security violation
{protect | recovery | restrict | shutdown}
no switchport port-security violation
When exceeding the maximum number of
the configured MAC addresses, MAC
address accessing the interface does not
belongs to this interface in MAC address
table or a MAC address is configured to
several interfaces in same VLAN, both of
them will violate the security of the MAC
address.
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21.5.1.3 Binding MAC Address Binding Troubleshooting
Enabling MAC address binding for ports may fail in some occasions. Here are some possible
causes and solutions:
If MAC address binding cannot be enabled for a port, make sure the port is not
enabling port aggregation and is not configured as a Trunk port. MAC address
binding is exclusive to such configurations. If MAC address binding is to be enabled,
the functions mentioned above must be disabled first.
If a secure address is set as static address and deleted, that secure address will be
unusable even though it exists. For this reason, it is recommended to avoid static
address for ports enabling MAC address.
21.6 MAC Notification Configuration
21.6.1 Introduction to MAC Notification
MAC Notification function depends on the notification. Add or remove the MAC address,
namely, when the device is added or removed, it will notify administrator about the change by
the trap function of SNMP.
21.6.2 MAC Notification Configuration
Mac notification configuration task list:
1. Configure the global SNMP MAC notification
2. Configure the global MAC notification
3. Configure the interval for sending MAC notification
4. Configure the size of history table
5. Configure the trap type of MAC notification supported by the port
6. Show the configuration and the data of MAC notification
7. Clear the statistics of MAC notification trap
1. Configure the global SNMP MAC notification
Command Explanation
Global Mode
snmp-server enable traps mac-notification Configure or cancel the global SNMP
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no snmp-server enable traps mac-notification MAC notification.
2. Configure the global MAC notification
Command Explanation
Global Mode
mac-address-table notification
no mac-address-table notification
Configure or cancel the global MAC
notification.
3. Configure the interval for sending MAC notification
Command Explanation
Global Mode
mac-address-table notification interval
<0-86400>
no mac-address-table notification interval
Configure the interval for sending the
MAC address notification, the no
command restores the default
interval.
4. Configure the size of history table
Command Explanation
Global Mode
mac-address-table notification history-size
<0-500>
no mac-address-table notification history-size
Configure the history table size, the
no command restores the default
value.
5. Configure the trap type of MAC notification supported by the port
Command Explanation
Port Mode
mac-notification {added | all | moved}
no mac-notification
Configure or cancel the trap type of
MAC notification supported by the
port.
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6. Show the configuration and the data of MAC notification
Command Explanation
Admin Mode
show mac-notification summary Show the configuration and the data
of MAC notification.
7. Clear the statistics of MAC notification trap
Command Explanation
Admin Mode
clear mac-notification statistics Clear the statistics of MAC
notification trap.
21.6.3 MAC Notification Example
IP address of network management station (NMS) is 1.1.1.5, IP address of Agent is 1.1.1.9.
NMS will receive Trap message from Agent. (Note: NMS may set the authentication to the
community character string of trap, suppose the community character string as usertrap)
Configuration procedure in the following:
Switch(config)#snmp-server enable
Switch(config)#snmp-server enable traps mac-notification
Switch(config)# mac-address-table notification
Switch(config)# mac-address-table notification interval 5
Switch(config)# mac-address-table notification history-size 100
Switch(Config-If-Ethernet1/4)# mac-notification both
21.6.4 MAC Notification Troubleshooting
Check whether trap message is sent successfully by show command and debug command of
SNMP.
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Chapter 22 MSTP Configuration
22.1 Introduction to MSTP
The MSTP (Multiple STP) is a new Spanning Tree Protocol which is based on the STP and the
RSTP. It runs on all the bridges of a bridged-LAN. It calculates a common and internal
spanning tree (CIST) for the bridge-LAN which consists of the bridges running the MSTP, the
RSTP and the STP. It also calculates the independent multiple spanning-tree instances (MSTI)
for each MST domain (MSTP domain). The MSTP, which adopts the RSTP for its rapid
convergence of the spanning tree, enables multiple VLANs to be mapped to the same
spanning-tree instance which is independent to other spanning-tree instances. The MSTP
provides multiple forwarding paths for data traffic and enables load balancing. Moreover,
because multiple VLANs share a same MSTI, the MSTP can reduce the number of
spanning-tree instances, which consumes less CPU resources and reduces the bandwidth
consumption.
22.2 MSTP Region
Because multiple VLANs can be mapped to a single spanning tree instance, IEEE 802.1s
committee raises the MST concept. The MST is used to make the association of a certain
VLAN to a certain spanning tree instance.
A MSTP region is composed of one or multiple bridges with the same MCID (MST
Configuration Identification) and the bridged-LAN (a certain bridge in the MSTP region is the
designated bridge of the LAN, and the bridges attaching to the LAN are not running STP). All
the bridges in the same MSTP region have the same MSID.
MSID consists of 3 attributes:
Configuration Name: Composed by digits and letters
Revision Level
Configuration Digest: VLANs mapping to spanning tree instances
The bridges with the above same 3 attributes are considered as in the same MST region.
When the MSTP calculates CIST in a bridged-LAN, an MSTP region is considered as a bridge.
See the figure below:
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22-118
Figure 22-1: Example of CIST and MST Region
In the above network, if the bridges are running the STP or the RSTP, one port between Bridge
M and Bridge B should be blocked. But if the bridges in the yellow range run the MSTP and are
configured in the same MST region, MSTP will treat this region as a bridge. Therefore, one
port between Bridge B and Root is blocked and one port on Bridge D is blocked.
MST
REGION
Root
M
F C
RootA A
DD
B
E
22.2.1 Operations within an MSTP Region
The IST connects all the MSTP bridges in a region. When the IST converges, the root of the
IST becomes the IST master, which is the switch within the region with the lowest bridge ID
and path cost to the CST root. The IST master is also the CST root if there is only one region
within the network. If the CST root is outside the region, one of the MSTP bridges at the
boundary of the region is selected as the IST master.
When an MSTP bridge initializes, it sends BPDUs claiming itself as the root of the CST and the
IST master, with both of the path costs to the CST root and to the IST master set to zero. The
bridge also initializes all of its MST instances and claims to be the root for all of them. If the
bridge receives superior MST root information (lower bridge ID, lower path cost, and so forth)
than currently stored for the port, it relinquishes its claim as the IST master.
Within a MST region, the IST is the only spanning-tree instance that sends and receives
BPDUs. Because the MST BPDU carries information for all instances, the number of BPDUs
that need to be processed by a switch to support multiple spanning-tree instances is
significantly reduced.
All MST instances within the same region share the same protocol timers, but each MST
instance has its own topology parameters, such as root switch ID, root path cost, and so forth.
22.2.1.1 Operations between MST Regions
If there are multiple regions or legacy 802.1D bridges within the network, MSTP establishes
and maintains the CST, which includes all MST regions and all legacy STP bridges in the
network. The MST instances combine with the IST at the boundary of the region to become the
CST.
The MSTI is only valid within its MST region. An MSTI has nothing to do with MSTIs in other
MST regions. The bridges in a MST region receive the MST BPDU of other regions through
Boundary Ports. They only process CIST related information and abandon MSTI information.
22.2.2 Port Roles
The MSTP bridge assigns a port role to each port which runs MSTP.
CIST port roles: Root Port, Designated Port, Alternate Port and Backup Port
On top of those roles, each MSTI port has one new role: Master Port.
The port roles in the CIST (Root Port, Designated Port, Alternate Port and Backup Port) are
defined in the same ways as those in the RSTP.
22.2.3 MSTP Load Balance
In an MSTP region, VLANs can by mapped to various instances. That can form various
topologies. Each instance is independent from the others and each distance can have its own
attributes such as bridge priority, port cost, etc. Consequently, the VLANs in different instances
have their own paths. The traffic of the VLANs are load-balanced.
22.3 MSTP Configuration Task List
MSTP configuration task list:
1. Enable the MSTP and set the running mode
2. Configure instance parameters
3. Configure MSTP region parameters
4. Configure MSTP time parameters
5. Configure the fast migrate feature for MSTP
6. Configure the format of port packet
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7. Configure the spanning-tree attribute of port
8. Configure the snooping attribute of authentication key
9. Configure the FLUSH mode once topology changes
1. Enable MSTP and set the running mode
Command Explanation
Global and Port Mode
spanning-tree
no spanning-tree Enable/Disable MSTP.
Global Mode
spanning-tree mode {mstp|stp|rstp}
no spanning-tree mode Set MSTP running mode.
Port Mode
spanning-tree mcheck Force port migrate to run under MSTP.
2. Configure instance parameters
Command Explanation
Global Mode
spanning-tree mst <instance-id> priority
<bridge-priority>
no spanning-tree mst <instance-id>
priority
Set bridge priority for specified instance.
spanning-tree priority <bridge-priority>
no spanning-tree priority
Configure the spanning-tree priority of the
switch.
Port Mode
spanning-tree mst <instance-id> cost
<cost>
no spanning-tree mst <instance-id> cost
Set port path cost for specified instance.
spanning-tree mst <instance-id>
port-priority <port-priority>
no spanning-tree mst <instance-id>
port-priority
Set port priority for specified instance.
spanning-tree mst <instance-id>
rootguard
no spanning-tree mst <instance-id>
rootguard
Configure currently port whether running
rootguard in specified instance, configure
the rootguard port can’t turn to root port.
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spanning-tree rootguard
no spanning-tree rootguard
Configure currently port whether running
rootguard in instance 0, configure the
rootguard port can’t turn to root port.
spanning-tree [mst <instance-id>]
loopguard
no spanning-tree [mst <instance-id>]
loopguard
Enable loopguard function on specified
instance, the no command disables this
function.
3. Configure MSTP region parameters
Command Explanation
Global Mode
spanning-tree mst configuration
no spanning-tree mst configuration
Enter MSTP region mode. The no
command restores the default setting.
MSTP Region Mode
instance <instance-id> vlan <vlan-list>
no instance <instance-id> [vlan <vlan-list> ]
Create Instance and set mapping
between VLAN and Instance.
name <name>
no name Set MSTP region name.
revision-level <level>
no revision-level Set MSTP region revision level.
abort
Quit MSTP region mode and return to
Global mode without saving MSTP
region configuration.
exit
Quit MSTP region mode and return to
Global mode with saving MSTP region
configuration.
no Cancel one command or set initial
value.
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4. Configure MSTP time parameters
Command Explanation
Global Mode
spanning-tree forward-time <time>
no spanning-tree forward-time
Set the value for switch forward delay
time.
spanning-tree hello-time <time>
no spanning-tree hello-time
Set the Hello time for sending BPDU
messages.
spanning-tree maxage <time>
no spanning-tree maxage Set Aging time for BPDU messages.
spanning-tree max-hop <hop-count>
no spanning-tree max-hop
Set Maximum number of hops of
BPDU messages in the MSTP region.
5. Configure the fast migrate feature for MSTP
Command Explanation
Port Mode
spanning-tree link-type p2p
{auto|force-true|force-false} Set the port link type.
no spanning-tree link-type
spanning-tree portfast [bpdufilter| bpduguard]
[recovery <30-3600>]
Set and cancel the port to be an
boundary port. bpdufilter receives the
BPDU discarding; bpduguard receives
the BPDU will disable port; no parameter
receives the BPDU, the port becomes a
non-boundary port.
no spanning-tree portfast
6. Configure the format of MSTP
Command Explanation
Port Mode
spanning-tree format standard
spanning-tree format privacy
spanning-tree format auto
no spanning-tree format
Configure the format of port
spanning-tree packet, standard format
is provided by IEEE, privacy is
compatible with CISCO and auto
means the format is determined by
checking the received packet.
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7. Configure the spanning-tree attribute of port
Command Explanation
Port Mode
spanning-tree cost
no spanning-tree cost Set the port path cost.
spanning-tree port-priority
no spanning-tree port-priority Set the port priority.
spanning-tree rootguard
no spanning-tree rootguard Set the port is root port.
Global Mode
spanning-tree transmit-hold-count
<tx-hold-count-value>
no spanning-tree transmit-hold-count
Set the max. transmit-hold-count of
port.
spanning-tree cost-format {dot1d | dot1t} Set port cost format with dot1d or
dot1t.
8. Configure the snooping attribute of authentication key
Command Explanation
Port Mode
spanning-tree digest-snooping
no spanning-tree digest-snooping
Set the port to use the authentication
string of partner port. The no
command restores to use the
generated string.
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9. Configure the FLUSH mode once topology changes
Command Explanation
Global Mode
spanning-tree tcflush {enable| disable|
protect}
no spanning-tree tcflush
Enable: the spanning-tree flush once
the topology changes.
Disable: the spanning tree don’t flush
when the topology changes.
Protect: the spanning-tree flush not
more than one time every ten seconds.
The no command restores to default
setting, enable flush once the topology
changes.
Port Mode
spanning-tree tcflush {enable| disable|
protect}
no spanning-tree tcflush
Configure the port flush mode.
The no command restores to use the
global configured flush mode.
22.4 MSTP Example
The following is a typical MSTP application example:
SW1
SW2 SW3
SW4
1
1 1
2
2 2X
3X3 4
4
5
5X
6 7
6X
7X
Figure 22-2: Typical MSTP Application Scenario
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The connections among the switches are shown in the above figure. All the switches run in the
MSTP mode by default, their bridge priority, port priority and port route cost are all in the
efault values (equal). The default configuration for switches is listed below:
d
Bridge Name SW1 SW2 SW3 SW4
Bridge MAC
Address
…00-00-01 …00-00-02 …00-00-03 …00-00-04
Bridge 8 8 8 2768 Priority 3276 3276 3276 3
port 1 128 128 128
port 2 128 128 128
port 3 128 128
port 4 128 128
port 5 128 128
port 6 128 128
Por
t Prio
rity
port 7 128 128
port 1 200000 200000 200000
port 2 200000 200000 200000
port 3 200000 200000
port 4 200000 200000
port 5 200000 200000
port 6 200000 200000
Rou
te C
ost
port 7 200000 200000
By default, the MSTP establishes a tree topology (in blue lines) rooted with Switch A. The ports
marked with “x” are in the discarding status, and the other ports are in the forwarding status.
itch 4.
ce 3; Map
Switch 3 as the root bridge of Instance 3; Set Switch 4 as the root bridge of
Set the bridge priority of Instance 4 in Switch 4 as 0.
Configurations Steps:
Step 1: Configure port to VLAN mapping:
Create VLAN 20, 30, 40, 50 in Switch 2, Switch 3 and Switch 4.
Set ports 1-7 as trunk ports in Switch 2 Switch 3 and Sw
Step 2: Set Switch 2, Switch 3 and Switch 4 in the same MSTP:
Set Switch 2, Switch 3 and Switch 4 to have the same region name as mstp.
Map VLAN 20 and VLAN 30 in Switch 2, Switch 3 and Switch 4 to Instan
VLAN 40 and VLAN 50 in Switch 2, Switch 3 and Switch 4 to Instance 4.
Step 3: Set
Instance 4
Set the bridge priority of Instance 3 in Switch 3 as 0.
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The detailed configuration is listed below:
Swi h 2:
exit
exit
exit
ation
nce 4 vlan 40;50
t
hport mode trunk
it
Switch2(config)#spanning-tree
witch 3:
exit
exit
exit
ation
nce 4 vlan 40;50
t
tc
Switch2(config)#vlan 20
Switch2(Config-Vlan20)#
Switch2(config)#vlan 30
Switch2(Config-Vlan30)#
Switch2(config)#vlan 40
Switch2(Config-Vlan40)#
Switch2(config)#vlan 50
Switch2(Config-Vlan50)#exit
Switch2(config)#spanning-tree mst configur
Switch2(Config-Mstp-Region)#name mstp
Switch2(Config-Mstp-Region)#instance 3 vlan 20;30
Switch2(Config-Mstp-Region)#insta
Switch2(Config-Mstp-Region)#exi
Switch2(config)#interface e1/1-7
Switch2(Config-Port-Range)#switc
Switch2(Config-Port-Range)#ex
S
Switch3(config)#vlan 20
Switch3(Config-Vlan20)#
Switch3(config)#vlan 30
Switch3(Config-Vlan30)#
Switch3(config)#vlan 40
Switch3(Config-Vlan40)#
Switch3(config)#vlan 50
Switch3(Config-Vlan50)#exit
Switch3(config)#spanning-tree mst configur
Switch3(Config-Mstp-Region)#name mstp
Switch3(Config-Mstp-Region)#instance 3 vlan 20;30
Switch3(Config-Mstp-Region)#insta
Switch3(Config-Mstp-Region)#exi
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Switch3(config)#interface e1/1-7
Switch3(Config-Port-Range)#switchport mode trunk
it
Switch3(config)#spanning-tree mst 3 priority 0
witch 4:
exit
exit
exit
ation
nce 4 vlan 40;50
t
hport mode trunk
it
Switch4(config)#spanning-tree mst 4 priority 0
he instance 0. The port 1 in
witch 2 is the master port of the instance 3 and the instance 4.
ly valid in
Switch3(Config-Port-Range)#ex
Switch3(config)#spanning-tree
S
Switch4(config)#vlan 20
Switch4(Config-Vlan20)#
Switch4(config)#vlan 30
Switch4(Config-Vlan30)#
Switch4(config)#vlan 40
Switch4(Config-Vlan40)#
Switch4(config)#vlan 50
Switch4(Config-Vlan50)#exit
Switch4(config)#spanning-tree mst configur
Switch4(Config-Mstp-Region)#name mstp
Switch4(Config-Mstp-Region)#instance 3 vlan 20;30
Switch4(Config-Mstp-Region)#insta
Switch4(Config-Mstp-Region)#exi
Switch4(config)#interface e1/1-7
Switch4(Config-Port-Range)#switc
Switch4(Config-Port-Range)#ex
Switch4(config)#spanning-tree
After the above configuration, Switch1 is the root bridge of the instance 0 of the entire network.
In the MSTP region which Switch 2, Switch 3 and Switch 4 belong to, Switch2 is the region root
of the instance 0, Switch3 is the region root of the instance 3 and Switch 4 is the region root of
the instance 4. The traffic of VLAN 20 and VLAN 30 is sent through the topology of the
instance 3. The traffic of VLAN 40 and VLAN 50 is sent through the topology of the instance 4.
And the traffic of other VLANs is sent through the topology of t
S
The MSTP calculation generates 3 topologies: the instance 0, the instance 3 and the instance
4 (marked with blue lines). The ports with the mark “x” are in the status of discarding. The other
ports are the status of forwarding. Because the instance 3 and the instance 4 are on
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the MSTP region; the following figure only shows the topology of the MSTP region.
Figure 22-3: The Topology Of the Instance 0 after the MSTP Calculation
Figure 22-4: The Topology Of the Instance 3 after the MSTP Calculation
Figure 22-5: The Topology Of the Instance 4 after the MSTP Calculation
SW1
SW2 SW3
SW4
1
1 1X
2
2 2
3X3 4
4
5
5X
6 7
6X
7X
2 2
SW2 SW3
3 3X 4
4X
5
5X
6 7
6
7X
SW4
2 2
SW2 SW3
X
3X3 4
4
5X
5
6 7X
6
7
SW4
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22.5 MSTP Troubleshooting
In order to run the MSTP on the switch port, the MSTP has to be enabled globally. If
the MSTP is not enabled globally, it can’t be enabled on the port.
The hould meet the
follo
o be sure about the changes
of the topologies. The global configuration is based on the bridge. Other
configurations are based on the individual instances.
MSTP parameters co-work with each other, so the parameters s
wing conditions. Otherwise, the MSTP may work incorrectly.
2×(Bridge_Forward_Delay -1.0 seconds) >= Bridge_Max._Age
Bridge_Max._Age >= 2 ×(Bridge_Hello_Time + 1.0 seconds)
When users modify the MSTP parameters, they have t
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Chapter 23 QoS Configuration
23.1 Introduction to QoS
QoS (Quality of Service) is a set of capabilities that allow you to create differentiated services
for network traffic, thereby providing better service for selected network traffic. QoS is a
guarantee for service quality of consistent and predictable data transfer service to fulfill
program requirements. QoS cannot generate extra bandwidth but provides more effective
bandwidth management according to the application requirement and network management
policy.
23.1.1 QoS Terms
QoS: Quality of Service provides a guarantee for service quality of consistent and predictable
data transfer service to fulfill program requirements. QoS cannot generate new bandwidth but
provides more effective bandwidth management according to the application requirement and
network management.
QoS Domain: QoS Domain supports QoS devices to form a net-topology that provides Quality
of Service, so this topology is defined as QoS Domain.
CoS: Class of Service, the classification information carried by Layer 2 802.1Q frames, taking
3 bits of the Tag field in frame header, is called user priority level in the range of 0 to 7.
Figure 23-1: CoS priority
ToS: Type of Service, a one-byte field carried in Layer 3 IPv4 packet header to symbolize the
service type of IP packets. Among ToS field can be IP Precedence value or DSCP value.
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Figure 23-2: ToS priority
IP Precedence: IP priority. Classification information carried in Layer 3 IP packet header,
occupying 3 bits, in the range of 0 to 7.
DSCP: Differentiated Services Code Point, classification information carried in Layer 3 IP
packet header, occupying 6 bits, in the range of 0 to 63, and is downward compatible with IP
Precedence.
MPLS TC(EXP)：
A field of the MPLS packets means the service class, there are 3 bits, the ranging from 0 to 7.
Internal Priority: The internal priority setting of the switch chip; its valid range relates with the
chip; short for Int-Prio or IntP.
Drop Precedence: When processing the packets, firstly drop the packets with the bigger drop
precedence, the ranging is 0-2 in three color algorithm, the ranging is 0-1 in dual color
algorithm. Short for Drop-Prec or DP.
Classification: The entry action of QoS, classifying packet traffic according to the
classification information carried in the packet and ACLs.
Policing: Ingress action of QoS that lays down the policing policy and manages the classified
packets.
Remark: Ingress action of QoS, perform allowing, degrading or discarding operations to
packets according to the policing policies.
Scheduling: QoS egress action. Configure the weight for eight egress queues WRR
(Weighted Round Robin).
In-Profile: Traffic within the QoS policing policy range (bandwidth or burst value) is called
In-Profile.
Out-of-Profile: Traffic out the QoS policing policy range (bandwidth or burst value) is called
Out-of-Profile.
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23.1.2 QoS Implementation
To implement the switch software QoS, a general, mature reference model should be given.
QoS cannot create new bandwidth, but can maximize the adjustment and configuration for the
current bandwidth resource. Fully implemented QoS can achieve complete management over
the network traffic. The following is as accurate as possible a description of QoS.
The data transfer specifications of IP cover only addresses and services of source and
destination, and ensure correct packet transmission using OSI layer 4 or above protocols such
as TCP. However, rather than provide a mechanism for providing and protecting packet
transmission bandwidth, IP provide bandwidth service by the best effort. This is acceptable for
services like Mail and FTP, but for increasing multimedia business data and e-business data
transmission, this best effort method cannot satisfy the bandwidth and low-lag requirement.
Based on differentiated service, QoS specifies a priority for each packet at the ingress. The
classification information is carried in Layer 3 IP packet header or Layer 2 802.1Q frame
header. QoS provides same service to packets of the same priority, while offers different
operations for packets of different priority. QoS-enabled switch or router can provide different
bandwidth according to the packet classification information, and can remark on the
classification information according to the policing policies configured, and may discard some
low priority packets in case of bandwidth shortage.
If devices of each hop in a network support differentiated service, an end-to-end QoS solution
can be created. QoS configuration is flexible, the complexity or simplicity depends on the
network topology and devices and analysis to incoming/outgoing traffic.
23.1.3 Basic QoS Model
The basic QoS consists of four parts: Classification, Policing, Remark and Scheduling, where
classification, policing and remark are sequential ingress actions, and Queuing and
Scheduling are QoS egress actions.
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Figure 23-3: Basic QoS Model
Classification: Classify traffic according to packet classification information and generate
internal priority and drop precedence based the classification information. For different packet
types and switch configurations, classification is performed differently; the flowchart below
explains this in detail.
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Figure 23-4: Classification process
Policing and remark: Each packet in classified ingress traffic is assigned an internal priority
value and a drop precedence value, and can be policed and remarked.
Policing can be performed based on the flow to configure different policies that allocate
bandwidth to classified traffic, the assigned bandwidth policy may be dual bucket dual color or
dual bucket three color. The traffic, will be assigned with different color, can be discarded or
passed, for the passed packets, add the remarking action. Remarking uses a new DSCP value
of lower priority to replace the original higher level DSCP value in the packet. The following
flowchart describes the operations.
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Figure 23-5: Policing and Remarking process
Queuing and scheduling: There are the internal priority and the drop precedence for the
egress packets; the queuing operation assigns the packets to different priority queues
according to the internal priority, while the scheduling operation perform the packet forwarding
according to the priority queue weight and the drop precedence. The following flowchart
describes the operations during queuing and scheduling.
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Figure 23-6: Queuing and Scheduling process
23.2 QoS Configuration Task List
Configure class map
Set up a classification rule according to ACL, CoS, VLAN ID, IPv4 Precedent, DSCP, IPV6 FL
to classify the data stream. Different classes of data streams will be processed with different
policies.
Configure a policy map
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After data steam classification, a policy map can be created to associate with the class map
created earlier and enter class mode. Then different policies (such as bandwidth limit, priority
degrading assigning new DSCP value) can be applied to different data streams. You can also
define a policy set that can be use in a policy map by several classes.
Apply QoS to the ports or the VLAN interfaces
Configure the trust mode for ports or bind policies to ports. A policy will only take effect on a
port when it is bound to that port.
The policy may be bound to the specific VLAN. It is not recommended to synchronously use
policy map on VLAN and its port. Configure queue management algorithms, such as sp，wrr，
wdrr，sp+wrr，sp+wdrr, and so on.
1. Configure class map.
Command Explanation
Global Mode
class-map <class-map-name>
no class-map <class-map-name>
Create a class map and enter class map
mode; the “no class-map
<class-map-name>” command deletes
the specified class map.
Class Map Mode
match {access-group <acl-index-or-name> |
ip dscp <dscp-list>| ip precedence
<ip-precedence-list>| ipv6 access-group
<acl-index-or-name> | ipv6 dscp <dscp-list>|
ipv6 flowlabel <flowlabel-list>|vlan
<vlan-list> | cos <cos-list> | c-vlan
<vlan-list>}
no match {access-group | ip dscp | ip
precedence | ipv6 access-group | ipv6 dscp |
ipv6 flowlabel | vlan | cos | c-vlan}
Set matching criterion (classify data
stream by ACL, CoS, VLAN ID, IPv4
Precedent, IPv6 FL or DSCP, etc) for the
class map; the no command deletes
specified matching criterion.
2. Configure a policy map
Command Explanation
Global Mode
policy-map <policy-map-name> Create a policy map and enter policy
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no policy-map <policy-map-name> map mode; the no command deletes the
specified policy map.
class-map <class-map-name> [insert-before
<class-map-name>]
no class <class-map-name>
After a policy map is created, it can be
associated to a class. Different policy or
new DSCP value can be applied to
different data streams in class mode; the
no command deletes the specified
class.
Policy Class-map Mode
set {ip dscp <new-dscp> | ip precedence
<new-precedence> | internal priority
<new-inp> | drop precedence <new-dp> | cos
<new-cos>}
no set {ip dscp | ip precedence | internal
priority | drop precedence |cos }
Assign a new internal priority for the
classified traffic; the no command
cancels the new assigned value.
Single Bucket Mode:
policy <bits_per_second>
<normal_burst_bytes> ({conform-action
ACTION | exceed-action ACTION} )
Dual Bucket Mode:
policy <bits_per_second>
<normal_burst_bytes> [pir <peak_rate_bps>]
| <maximum_burst_bytes> [{conform-action
ACTION | exceed-action ACTION |
violate-action ACTION }]
ACTION definition:
drop | transmit | set-dscp-transmit
<dscp_value> | set-prec-transmit
<ip_precedence_value> | set-cos-transmit
<cos_value> | set-internal-priority
<inp_value> | set-Drop-Precedence
<dp_value>
no policy
Configure a policy for the classified flow.
The non-aggregation policy command
supporting three colors. Determine
whether the working mode of token
bucket is singe rage single bucket,
single rate dual bucket or dual rate dual
bucket, set the corresponding action to
the different color packets. The no
command will delete the mode
configuration.
accounting
no accounting
Set statistic function for the classified
traffic. After enable this function under
the policy class map mode, add statistic
function to the traffic of the policy class
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map. In single bucket mode, the
messages can be only red or green
when passing policy. When printing the
information, in-profile means green and
out-profile means red; In dual bucket
mode, there are three colors(green,
yellow, red) of messages. in-profile
means green, out-profile means red and
yellow.
drop
no drop
transmit
no transmit
Drop or transmit the traffic that match
the class, the no command cancels the
assigned action.
3. Apply QoS to port or VLAN interface
Command Explanation
Port Mode
mls qos trust dscp
no mls qos trust dscp
Configure port trust; the no command
disables the current trust status of the
port.
mls qos cos {<default-cos>}
no mls qos cos
Configure the default CoS value of the
port; the no command restores the
default setting.
service-policy input <policy-map-name>
no service-policy input {<policy-map-name>}
Apply a policy map to the specified port;
the no command deletes the specified
policy map applied to the port or deletes
all the policy maps applied on the
ingress direction of the port . Egress
policy map is not supported yet.
Global Mode
service-policy input <policy-map-name> vlan
<vlan-list>
no service-policy input {<policy-map-name>}
vlan <vlan-list>
Apply a policy map to the specified
VLAN interface; the no command
deletes the specified policy map applied
to the VLAN interface or deletes all the
policy maps applied in the ingress
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direction of the vlan interface .
4. Configure queue management algorithm and weight
Command Explanation
Port Mode
mls qos queue algorithm {sp | wrr | wdrr}
no mls qos queue algorithm
Set queue management algorithm, the
default queue management algorithm is
wrr.
mls qos queue wrr weight
<weight0..weight7>
no mls qos queue wrr weight
Set queue weight based a port, the
default queue weight is 1 2 3 4 5 6 7 8.
mls qos queue wdrr weight
<weight0..weight7>
no mls qos queue wdrr weight
Configure the queue weight according to
the port. The queue weight is 10 20 40
80 160 320 640 1280 as default.
mls qos queue <queue-id> bandwidth
<minimum-bandwidth>
<maximum-bandwidth>
no mls qos queue <queue-id> bandwidth
Configure the bandwidth pledge
according to the port. The range is kbit/s
and the granularity is 64kbit.
5. Configure QoS mapping
Command Explanation
Global Mode
mls qos map {cos-intp <intp1…intp8> |
cos-dp<dp1…dp8> | dscp-intp <in-dscp list>
to <intp> | dscp-dp <in-dscp list> to <dp> |
dscp-dscp <in-dscp list> to <out-dscp>}
no mls qos map {cos-intp | cos-dp | dscp-intp
| dscp-dp | dscp-dscp}
Set the priority mapping for QoS, the no
command restores the default mapping
value.
6. Clear accounting data of the specific ports or VLANs
Command Explanation
Admin Mode
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clear mls qos statistics [in
<vlan-id>/<interface> | interface
<interface-name> | vlan <vlan-id>]
Clear accounting data of the specified
ports or VLAN Policy Map. If there are
no parameters, clear accounting data
of all policy map.
7. Show configuration of QoS
Command Explanation
Admin Mode
show mls qos maps [cos-intp | dscp-intp] Display the configuration of QoS mapping.
show class-map [<class-map-name>] Display the classified map information of
QoS.
show policy-map [<policy-map-name>] Display the policy map information of
QoS.
show mls qos {interface [<interface-id>]
[policy | queuing] | vlan <vlan-id>}
Display QoS configuration information on
a port.
23.3 QoS Example
Example 1:
Enable QoS function to change the queue out weight of port to 1:1:2:2:4:4:8:8; set it in trust
CoS mode and set the default CoS value of the port to 5.
The configuration steps are listed below:
Switch#config
Switch(config)#mls qos queue weight 1 1 2 2
Switch(Config-If-Ethernet1/1)# mls qos queue wrr weight 1 1 2 2 4 4 8 8
Switch(Config-If-Ethernet1/1)#mls qos cos 5
Configuration result:
When QoS is enabled in Global Mode, the egress queue bandwidth proportion of all ports is
1:1:2:2:4:4:8:8. When packets with CoS value coming in through port, it will be mapped to the
queue out according to the CoS value; CoS value 0 to 7 corresponds to queue out 0, 0, 1, 1, 2,
2, 3, 3 respectively. If the incoming packet without CoS value, it is defaulted to 5 and will be put
in queue 2.
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Example 2:
In port ethernet1/2, set the bandwidth for packets from segment 192.168.1.0 to 10 Mb/s, with a
burst value of 4 MB; all packets exceed this bandwidth setting will be dropped.
The configuration steps are listed below:
Switch#config
Switch(config)#access-list 1 permit 192.168.1.0 0.0.0.255
Switch(config)#class-map c1
Switch(Config-ClassMap-c1)#match access-group 1
Switch(Config-ClassMap-c1)#exit
Switch(config)#policy-map p1
Switch(Config-PolicyMap-p1)#class c1
Switch(Config-PolicyMap-p1-Class-c1)#policy 10000 4000 exceed-action drop
Switch(Config-PolicyMap-p1-Class-c1)#exit
Switch(Config-PolicyMap-p1)#exit
Switch(config)#interface ethernet 1/2
Switch(Config-If-Ethernet1/2)#service-policy input p1
Configuration result:
An ACL name 1 is set to matching segment 192.168.1.0. Enable QoS globally, create a class
map named c1, matching ACL1 in class map; create another policy map named p1 and refer
to c1 in p1, set appropriate policies to limit bandwidth and burst value. Apply this policy map on
port ethernet1/2. After the above settings done, bandwidth for packets from segment
192.168.1.0 through port ethernet 1/2 is set to 10 Mb/s, with a burst value of 4 MB, all packets
exceed this bandwidth setting in that segment will be dropped.
Example 3:
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Server
Switch 3
Switch 2
Trunk
QoS area
Switch 1
Figure 23-7: Typical QoS topology
As shown in the figure, inside the block is a QoS domain, Switch 1 classifies different traffics
and assigns different IP precedences. For example, set CoS precedence for packets from
segment 192.168.1.0 to 5 on port ethernet1/1. The port connecting to switch 2 is a trunk port.
In Switch 2, set port ethernet 1/1 that connecting to swtich1 to trust cos. Thus inside the QoS
domain, packets of different priorities will go to different queues and get a different bandwidth.
The configuration steps are listed below:
QoS configuration in Switch1:
Switch#config
Switch(config)#access-list 1 permit 192.168.1.0 0.0.0.255
Switch(config)#class-map c1
Switch(Config-ClassMap-c1)#match access-group 1
Switch(Config-ClassMap-c1)#exit
Switch(config)#policy-map p1
Switch(Config-PolicyMap-p1)#class c1
Switch(Config-PolicyMap-p1-Class-c1)#set ip precedence 5
Switch(Config-PolicyMap-p1-Class-c1)#exit
Switch(Config-PolicyMap-p1)#exit
Switch(config)#interface ethernet 1/1
Switch(Config-If-Ethernet1/1)#service-policy input p1
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QoS configuration in Switch2:
Switch#config
Switch(config)#interface ethernet 1/1
Switch(Config-If-Ethernet1/1)#mls qos trust cos
23.4 QoS Troubleshooting
trust cos can be used with other trust or Policy Map.
trust dscp can be used with other trust or Policy Map. This configuration takes effect
to IPv4 and IPv6 packets.
trust dscp and trust cos may be configured at the same time, the priority is:
DSCP>COS.
If the dynamic VLAN (mac vlan/voice vlan/ip subnet vlan/protocol vlan) is configured,
then the packet COS value equals COS value of the dynamic VLAN.
Policy map can only be bound to ingress direction, egress is not supported yet.
At present, it is not recommended to synchronously use policy map on VLAN and
VLAN’s port.
Chapter 24 Flow-based Redirection
24.1 Introduction to Flow-based Redirection
Flow-based redirection function enables the switch to transmit the data frames meeting
some special condition (specified by ACL) to another specified port. The fames meeting a
same special condition are called a class of flow, the ingress port of the data frame is called
the source port of redirection, and the specified egress port is called the destination port of
redirection. Usually there are two kinds of application of flow-based redirection:
1. Connecting a protocol analyzer (for example, Sniffer) or a RMON monitor to the
destination port of redirection, to monitor and manage the network, and diagnose the
problems in the network;
2. Special transmission policy for a special type of data frames.
The switch can only designate a single destination port of redirection for a same class of
flow within a source port of redirection, while it can designate different destination ports of
redirection for different classes of flows within a source port of redirection. The same class of
flow can be applied to different source ports.
24.2 Flow-based Redirection Configuration Task
Sequence
1． Flow-based redirection configuration
2． Check the current flow-based redirection configuration
1. Flow-based redirection configuration
Command Explanation
Port Mode
access-group <aclname> redirect to interface
[ethernet <IFNAME>|<IFNAME>]
no access-group <aclname> redirect
Specify flow-based redirection
for the port; the “no
access-group <aclname>
redirect” command is used to
delete flow-based redirection.
24-1
2. Check the current flow-based redirection configuration
Command Explanation
Admin / Global Mode
show flow-based-redirect {interface [ethernet
<IFNAME> |<IFNAME>]}
Display the information of
current flow-based redirection
in the system/port.
24.3 Flow-based Redirection Examples
Example:
User’s request of configuration is listed as follows: redirecting the frames whose source IP is
192.168.1.111 received from port 1 to port 6, that is sending the frames whose source IP is
192.168.1.111 received from port 1 through port6.
Modification of configuration:
1: Set an ACL, the condition to be matched is: source IP is 192.168.1.111;
2: Apply the redirection based on this flow to port 1.
The following is the configuration procedure:
Switch(config)#access-list 1 permit host 192.168.1.111
Switch(config)#interface ethernet 1/1
Switch(Config-If-Ethernet1/1)# access-group 1 redirect to interface ethernet 1/6
24.4 Flow-based Redirection Troubleshooting Help
When the configuration of flow-based redirection fails, please check whether it is the
following reasons causing the problem:
The type of flow (ACL) can only be digital standard IP ACL, digital extensive IP ACL,
nomenclature standard IP ACL, nomenclature extensive IP ACL, digital standard
MAC ACL, digital extensive MAC ACL, nomenclatural standard MAC ACL,
nomenclatural extensive MAC ACL, digital standard IPv6 ACL, and nomenclature
standard IPv6 ACL; Parameters of Timerange and Portrange cannot be set in ACL; the type of ACL
24-2
should be permitted.
The redirection port must be 1000Mb port in the flow-based redirection function.
Chapter 25 Flexible QinQ Configuration
25.1 Introduction to Flexible QinQ
25.1.1 Q-in-Q Technique
Dot1q-tunnel is also called Q-in-Q (802.1Q-in-802.1Q), which is an expansion of 802.1Q. Its
dominating idea is encapsulating the customer VLAN tag (CVLAN tag) to the service provider
VLAN tag (SPVLAN tag). The packet with two VLAN tags is transmitted through the backbone
network of the ISP internet to provide a simple Layer 2 tunnel for the users. It is simple and
easy to manage, applicable only by static configuration, and especially adaptive to small office
network or small metropolitan area network using Layer 3 switch as backbone equipment.
There are two kinds of Q-in-Q: basic Q-in-Q and flexible Q-in-Q, the priority of flexible Q-in-Q is
higher than basic Q-in-Q.
25.1.2 Basic Q-in-Q
Basic Q-in-Q based port. After a port configures Q-in-Q, whether the received packet with tag
or not, the device still packs the default VLAN tag for the packet. Using basic Q-in-Q is simple,
but the setting method of VLAN tag is inflexible.
25.1.3 Flexible Q-in-Q
Flexible Q-in-Q based data flow. It selects whether pack the external tag and packs what kind
of the external tag by matching the material flow. For example, implement the property of
flexible Q-in-Q according to the user’s VLAN tag, MAC address, IPv4/IPv6 address, IPv4/IPv6
protocol and the port ID of the application, etc. So, it can encapsulate the external tag for the
packet and implements different scheme by different users or methods.
25.1.4 Flexible Q-in-Q Configuration Task List
The match of flexible Q-in-Q data flow uses policy-map rule of QoS to be sent; the
25-3
configuration task list is as follows:
1. Create class-map to classify different data flows
2. Create flexible QinQ policy-map to relate with the class-map and set the corresponding
operation
3. Bind flexible QinQ policy-map to port
1. Configure class map
Command Explanation
Global Mode
class-map <class-map-name>
no class-map <class-map-name>
Create a class-map and enter
class-map mode, the no command
deletes the specified class-map.
Class-map Mode
match {access-group <acl-index-or-name> |
ip dscp <dscp-list>| ip precedence
<ip-precedence-list>| ipv6 access-group
<acl-index-or-name>| ipv6 dscp <dscp-list> |
ipv6 flowlabel <flowlabel-list> | vlan
<vlan-list> | cos <cos-list> | c-vlan
<vlan-list>}
no match {access-group | ip dscp | ip
precedence|ipv6 access-group| ipv6 dscp |
ipv6 flowlabel | vlan | cos | c-vlan}
Set the match standard of class-map,
(classify data flow by ACL, IPv4
Precedent or DSCP, etc for the class
map); the no command deletes the
specified match standard.
2. Configure policy-map of flexible QinQ
Command Explanation
Global Mode
policy-map <policy-map-name>
no policy-map <policy-map-name>
Create a policy-map and enter
policy-map mode, the no command
deletes the specified policy-map.
class <class-map-name> [insert-before
<class-map-name>]
no class <class-map-name>
After a policy-map is created, it can be
associated to a class. Different policy
or new DSCP value can be applied to
different data flows in class mode; the
no command deletes the specified
class-map.
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Policy Class-map Mode
set {s-vid <new-vid>}
no set {s-vid }
Assign the new cos and vid value to the
packets which match the class map, no
command cancels the operation.
3. Bind flexible Q-in-Q policy-map to port
Command Explanation
Port Mode
service-policy input <policy-map-name>
no service-policy input <policy-map-name>
Apply a policy-map to a port, the no
command deletes the specified
policy-map applied to the port.
4. Show flexible Q-in-Q policy-map bound to port
Command Explanation
Admin Mode
show mls qos {interface ethernet
[<interface-id>]
Show flexible Q-in-Q configuration on the
port.
25.2 Flexible Q-in-Q Example
Insert Metropolitan Area Network Platform
Metropolitan Area Core Network
DSLAM1
DSLAM2
BRAS SR
Broad Band
VOIP
Video order programme
DSCP
DSCP
DSCP
10
20
30
1001
2001
3001
1001
2001
3001
TAG
TAG
TAG
TAG
TAG
TAG
DSCP
DSCP
DSCP
10
20
30
DSCP
DSCP
DSCP
10
20
30
DSCP
DSCP
DSCP
10
20
30
25-5
Figure 25-1: Flexible Q-in-Q application topology
As shown in the figure, the first user is assigned three DSCPs that the values are 10, 20, 30
respectively in DSLAM1. DSCP10 corresponds to Broad Band Network, DSCP20 corresponds
to VOIP, DSCP30 corresponds to VOD. After the downlink port enables flexible QinQ function,
the packets will be packed with different external tags according to DSCP of users. DSCP10
will be packed an external tag 1001 (This tag is unique in public network), enter Broad Band
Network-DSCP10 and classfied to BRAS device. DSCP20 (or DSCP30) will be packed an
external VLAN tag 2001(or 3001) and classfied to SR device according to the flow rules. The
second user can be assigned different DSCPs in DSLAM2. Notice: The assigned DSCP of the
second user may be same with the first user and the DSCP value will be also packed an
external tag. In the above figure, the external tag of the second user is different to the first user
for distinguishing DSLAM location and locating the user finally.
The configuration in the following:
If the data flow of DSLAM1 enters the switch’s downlink port1, the configuration is as follows:
Switch(config)#class-map c1
Switch(config-classmap-c1)#match ip dscp 10
Switch(config-classmap-c1)#exit
Switch(config)#class-map c2
Switch(config-classmap-c2)#match ip dscp 20
Switch(config-classmap-c2)#exit
Switch(config)#class-map c3
Switch(config-classmap-c3)#match ip dscp 30
Switch(config-classmap-c3)#exit
Switch(config)#policy-map p1
Switch(config-policymap-p1)#class c1
Switch(config-policymap-p1-class-c1)# set s-vid 1001
Switch(config-policymap-p1)#class c2
Switch(config-policymap-p1-class-c2)# set s-vid 2001
Switch(config-policymap-p1)#class c3
Switch(config-policymap-p1-class-c3)# set s-vid 3001
Switch(config-policymap-p1-class-c3)#exit
Switch(config-policymap-p1)#exit
Switch(config)#interface ethernet 1/1
Switch(config-if-ethernet1/1)#dot1q-tunnel enable
Switch(config-if-ethernet1/1)#service-policy p1 in
25-6
25.3 Flexible Q-in-Q Troubleshooting
If flexible Q-in-Q policy cannot be bound to the port, please check whether the problem is
caused by the following reasons:
Make sure flexible Q-in-Q whether supports the configured class-map and
policy-map
Make sure ACL includes permit rule if the class-map matches ACL rule
Make sure the switch exists enough TCAM resource to send the binding
Chapter 26 Layer 3 Management
Configuration
Switch only support Layer 2 forwarding, but can configure a Layer 3 management port for the
communication of all kinds of management protocols based on IP Protocol.
26.1 Layer 3 Management Interface
26.1.1 Introduction to Layer 3 Management Interface
Only one Layer 3 management interface can be created on switch. The Layer 3 interface is not
a physical interface but a virtual interface. Layer 3 interface is built on VLANs. The Layer 3
interface can contain one or more Layer 2 ports which belong to the same VLAN, or contain no
Layer 2 ports. At least one of the Layer 2 ports contained in Layer 3 interface should be in UP
state for Layer 3 interface in UP state, otherwise, Layer 3 interface will be in DOWN state. The
switch can use the IP addresses set in the Layer 3 management interface to communicate with
the other devices via IP.
26.1.2 Layer 3 Interface Configuration Task List
Layer 3 Interface Configuration Task List:
1. Create Layer 3 management interface
2. Configure VLAN interface description
1. Create Layer 3 Management Interface
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Command Explanation
Global Mode
interface vlan <vlan-id>
no interface vlan <vlan-id>
Creates a management VLAN interface; the no command
deletes the VLAN interface created in the switch.
2. Configure VLAN interface description
Command Explanation
VLAN Interface Mode
description <text>
no description
Configure the description information of VLAN interface.
The no command will cancel the description information of
VLAN interface.
26.2 IP Configuration
26.2.1 Introduction to IPv4, IPv6
IPv4 is the current version of global universal Internet protocol. The practice has proved that
IPv4 is simple, flexible, open, stable, strong and easy to implement while collaborating well
with various protocols of upper and lower layers. Although IPv4 almost has not been changed
since it was established in 1980’s, it has kept growing to the current global scale with the
promotion of Internet. However, as Internet infrastructure and Internet application services
continue boosting, IPv4 has shown its deficiency when facing the present scale and
complexity of Internet.
IPv6 refers to the sixth version of Internet protocol which is the next generation Internet
protocol designed by IETF to replace the current Internet protocol version 4 (IPv4). IPv6 was
specially developed to make up the shortages of IPv4 addresses so that Internet can develop
further.
The most important problem IPv6 has solved is to add the amount of IP addresses. IPv4
addresses have nearly run out, whereas the amount of Internet users has been increasing in
geometric series. With the greatly and continuously boosting of Internet services and
application devices (Home and Small Office Network, IP phone and Wireless Service
Information Terminal which make use of Internet,) which require IP addresses, the supply of IP
addresses turns out to be more and more tense. People have been working on the problem of
26-8
shortage of IPv4 addresses for a long time by introducing various technologies to prolong the
lifespan of existing IPv4 infrastructure, including Network Address Translation(NAT for short),
and Classless Inter-Domain Routing(CIDR for short), etc.
Although the combination of CIDR, NAT and private addressing has temporarily mitigated the
problem of IPv4 address space shortage, NAT technology has disrupted the end-to-end model
which is the original intention of IP design by making it necessary for router devices that serve
as network intermediate nodes to maintain every connection status which increases network
delay greatly and decreases network performance. Moreover, the translation of network data
packet addresses baffles the end-to-end network security check, IPSec authentication header
is such an example.
Therefore, in order to solve all kinds of problems existing in IPv4 comprehensively, the next
generation Internet Protocol IPv6 designed by IETF has become the only feasible solution at
present.
First of all, the 128 bits addressing scheme of IPv6 Protocol can guarantee to provide enough
globally unique IP addresses for global IP network nodes in the range of time and space.
Moreover, besides increasing address space, IPv6 also enhanced many other essential
designs of IPv4.
Hierarchical addressing scheme facilitates Route Aggregation, effectively reduces route table
entries and enhances the efficiency and expansibility of routing and data packet processing.
The header design of IPv6 is more efficient compared with IPv4. It has less data fields and
takes out header checksum, thus expedites the processing speed of basic IPv6 header. In
IPv6 header, fragment field can be shown as an optional extended field, so that data packets
fragmentation process won’t be done in router forwarding process, and Path MTU Discovery
Mechanism collaborates with data packet source which enhances the processing efficiency of
router.
Address automatic configuration and plug-and-play is supported. Large amounts of hosts can
find network routers easily by address automatic configuration function of IPv6 while obtaining
a globally unique IPv6 address automatically as well which makes the devices using IPv6
Internet plug-and-play. Automatic address configuration function also makes the readdressing
of existing network easier and more convenient, and it is more convenient for network
operators to manage the transformation from one provider to another.
Support IPSec. IPSec is optional in IPv4, but required in IPv6 Protocol. IPv6 provides security
extended header, which provides end-to-end security services such as access control,
26-9
confidentiality and data integrity, consequently making the implement of encryption, validation
and Virtual Private Network easier.
Enhance the support for Mobile IP and mobile calculating devices. The Mobile IP Protocol
defined in IETF standard makes mobile devices movable without cutting the existing
connection, which is a network function getting more and more important. Unlike IPv4, the
mobility of IPv6 is from embedded automatic configuration to get transmission address
(Care-Of-Address); therefore it doesn’t need Foreign Agent. Furthermore, this kind of binding
process enables Correspondent Node communicate with Mobile Node directly, thereby avoids
the extra system cost caused by triangle routing choice required in IPv4.
Avoid the use of Network Address Translation. The purpose of the introduction of NAT
mechanism is to share and reuse same address space among different network segments.
This mechanism mitigates the problem of the shortage of IPv4 address temporally; meanwhile
it adds the burden of address translation process for network device and application. Since the
address space of IPv6 has increased greatly, address translation becomes unnecessary, thus
the problems and system cost caused by NAT deployment are solved naturally.
Support extensively deployed Routing Protocol. IPv6 has kept and extended the supports for
existing Internal Gateway Protocols (IGP for short), and Exterior Gateway Protocols (EGP for
short). For example, IPv6 Routing Protocol such as RIPng, OSPFv3, IS-ISv6 and MBGP4+,
etc.
Multicast addresses increased and the support for multicast has enhanced. By dealing with
IPv4 broadcast functions such as Router Discovery and Router Query, IPv6 multicast has
completely replaced IPv4 broadcast in the sense of function. Multicast not only saves network
bandwidth, but enhances network efficiency as well.
26.2.2 IP Configuration
Layer 3 interface can be configured as IPv4 interface and IPv6 interface.
26.2.2.1 IPv4 Address Configuration
IPv4 address configuration task list:
1. Configure the IPv4 address of three-layer interface
2. Configure the default gateway
26-10
1． Configure the IPv4 address of three-layer interface
Command Explanation
VLAN Interface Mode
ip address <ip-address> <mask> [secondary]
no ip address [<ip-address> <mask>]
Configure IP address of VLAN
interface; the no ip address
[<ip-address> <mask>] command
cancels IP address of VLAN
interface.
26-11
26.2.2.2 IPv6 Address Configuration
The configuration Task List of IPv6 is as follows:
1. IPv6 basic configuration
(1) Configure interface IPv6 address
(2) Configure default gateway
2. IPv6 Neighbor Discovery Configuration
(1) Configure DAD neighbor solicitation message number
(2) Configure send neighbor solicitation message interval
(3) Configure static IPv6 neighbor entries
(4) Delete all entries in IPv6 neighbor table
1. IPv6 Basic Configuration
(1) Configure interface IPv6 address
Command Explanation
VLAN Interface Mode
ipv6 address
<ipv6-address/prefix-length>
[eui-64]
no ipv6 address
<ipv6-address/prefix-length>
Configure IPv6 address, including aggregatable
global unicast addresses, site-local addresses
and link-local addresses. The no ipv6 address
<ipv6-address/prefix-length> command
cancels IPv6 address.
2. IPv6 Neighbor Discovery Configuration
(1) Configure DAD Neighbor solicitation Message number
Command Explanation
VLAN Interface Mode
ipv6 nd dad attempts <value>
no ipv6 nd dad attempts
Set the neighbor query message number sent in
sequence when the interface makes duplicate
address detection. The no command resumes
default value (1).
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(2) Configure Send Neighbor solicitation Message Interval
Command Explanation
VLAN Interface Mode
ipv6 nd ns-interval <seconds>
no ipv6 nd ns-interval
Set the interval of the interface to send neighbor
query message. The NO command resumes
default value (1 second).
(3) Configure static IPv6 neighbor Entries
Command Explanation
VLAN Interface Mode
ipv6 neighbor <ipv6-address>
<hardware-address> interface
<interface-type interface-name>
Set static neighbor table entries, including
neighbor IPv6 address, MAC address and
two-layer port.
no ipv6 neighbor <ipv6-address> Delete neighbor table entries.
26.2.3 IPv6 Troubleshooting
If the connected PC has not obtained IPv6 address, you should check the RA
announcement switch (the default is turned off)
26.3 Static Route
26.3.1 Introduction to Static Route
As mentioned earlier, the static route is the manually specified path to a network or a host.
Static route is simple and consistent, and can prevent illegal route modification, and is
convenient for load balance and route backup. However, it also has its own defects. Static
route, as its name indicates, is static, it won’t modify the route automatically on network failure,
and manual configuration is required on such occasions, therefore it is not suitable for mid and
large-scale networks.
Static route is mainly used in the following two conditions: 1) in stable networks to reduce load
of route selection and routing data streams. For example, static route can be used in route to
STUB network. 2) For route backup, configure static route in the backup line, with a lower
priority than the main line.
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Static route and dynamic route can coexist; Layer 3 switch will choose the route with the
highest priority according to the priority of routing protocols. At the same time, static route can
be introduced (redistribute) in dynamic route, and change the priority of the static route
introduced as required.
26.3.2 Introduction to Default Route
Default route is a kind of static route, which is used only when no matching route is found. In
the route table, default route in is indicated by a destination address of 0.0.0.0 and a network
mask of 0.0.0.0, too. If the route table does not have the destination of a packet and has no
default route configured, the packet will be discarded, and an ICMP packet will be sent to the
source address indicate the destination address or network is unreachable.
26.3.3 Static Route Configuration Task List
1. Static route configuration
1. Static route configuration
Command Explanation
Global Mode
ip route {<ip-prefix> <mask> |
<ip-prefix>/<prefix-length>} {<gateway-address> |
<gateway-interface>} [<distance>]
no ip route {<ip-prefix> <mask> |
<ip-prefix>/<prefix-length>} [<gateway-address> |
<gateway-interface>] [<distance>]
Set static routing; the no ip
route {<ip-prefix> <mask> |
<ip-prefix>/<prefix-length>}
[<gateway-address> |
<gateway-interface>]
[<distance>] command deletes
a static route entry
26.3.4 Static Route Configuration Examples
The figure shown below is a simple network consisting of three Layer 3 switches, the network
mask for all switches and PC is 255.255.255.0. PC-A and PC-C are connected via the static
route set in SwtichA and SwitchC; PC3 and PC-B are connected via the static route set in
SwtichC to SwitchB; PC-B and PC-C is connected via the default route set in SwitchB.
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Switch B
PC-A:10.1.1.2 PC-B:10.1.4.2
vlan3:10.1.5.1
vlan1:10.1.1.1
vlan2:10.1..2.1
vlan2:10.1.4.1
vlan2:10.1.2.2 vlan1:10.1.3.2
Switch A
Switch C
vlan1:10.1.3.1
PC-C:10.1.5.2
Figure 26-1: Static Route Configurations
Configuration steps:
Configuration of Layer 3 SwitchA
Switch#config
Switch (config) #ip route 10.1.5.0 255.255.255.0 10.1.2.2
Configuration of Layer 3 SwitchC
Switch#config
Next hop use the partner IP address
Switch(config)#ip route 10.1.1.0 255.255.255.0 10.1.2.1
Next hop use the partner IP address
Switch(config)#ip route 10.1.4.0 255.255.255.0 10.1.3.1
Configuration of Layer 3 SwitchB
Switch#config
Switch(config)#ip route 0.0.0.0 0.0.0.0 10.1.3.2
In this way, ping connectivity can be established between PC-A and PC-C, and PC-B and
PC-C.
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26.4 RIP
26.4.1 Introduction to RIP
RIP is first introduced in ARPANET, this is a protocol dedicated to small, simple networks. RIP
is a distance vector routing protocol based on the Bellman-Ford algorithm. Network devices
running vector routing protocol send two kind of information to the neighboring devices
regularly:
• Number of hops to reach the destination network, or metrics to use or number of networks to
pass.
• What is the next hop, or the director (vector) to use to reach the destination network.
The distance vector Layer 3 switch send all their route selecting tables to the neighbor Layer 3
switches at regular interval. A Layer 3 switch will build their own route selecting information
table based on the information received from the neighbor Layer 3 switches. Then, it will send
this information to its own neighbor Layer 3 switches. As a result, the route selection table is
built on second hand information, route beyond 15 hops will be deemed as unreachable.
RIP protocol is an optional routing protocol based on UDP. Hosts using RIP send and receive
packets on UDP port 520. All Layer 3 switches running RIP send their route table to all
neighbor Layer 3 switches every 30 seconds for update. If no information from the partner is
received in 180 seconds, then the device is deemed to have failed and the network connected
to that device is considered to be unreachable. However, the route of that Layer 3 switch will
be kept in the route table for another 120 seconds before deletion.
As Layer 3 switches running RIP built route table with second hand information, infinite count
may occur. For a network running RIP routing protocol, when an RIP route becomes
unreachable, the neighboring RIP Layer 3 switch will not send route update packets at once,
instead, it waits until the update interval timeout (every 30 seconds) and sends the update
packets containing that route. If before it receives the updated packet, its neighbors send
packets containing the information about the failed neighbor, “infinite count” will be resulted. In
other words, the route of unreachable Layer 3 switch will be selected with the metrics
increasing progressively. This greatly affects the route selection and route aggregation time.
To prevent “infinite count”, RIP provides mechanism such as “split horizon” and “triggered
update” to solve route loop. “Split horizon” is done by avoiding sending to a gateway routes
leaned from that gateway. There are two split horizon methods: “simple split horizon” and
“poison reverse split horizon”. Simple split horizon deletes from the route to be sent to the
neighbor gateways the routes learnt from the neighbor gateways; poison reverse split horizon
not only deletes the abovementioned routes, but set the costs of those routes to infinite.
“Triggering update” mechanism defines whenever route metric changed by the gateway, the
gateway advertise the update packets immediately, regardless of the 30 second update timer
status.
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There two versions of RIP, version 1 and version 2. RFC1058 introduces RIP-I protocol,
RFC2453 introduces RIP-II, which is compatible with RFC1723 and RFC1388. RIP-I updates
packets by packets broadcast, subnet mask and authentication is not supported. Some fields
in the RIP-I packets are not used and are required to be all 0’s; for this reason, such all 0's
fields should be checked when using RIP-I, the RIP-I packets should be discarded if such
fields are non-zero. RIP-II is a more improved version than RIP-I. RIP-II sends route update
packets by multicast packets (multicast address is 224.0.0.9). Subnet mask field and RIP
authentication filed (simple plaintext password and MD5 password authentication are
supported), and support variable length subnet mask. RIP-II used some of the zero field of
RIP-I and require no zero field verification. switch send RIP-II packets in multicast by default,
both RIP-I and RIP-II packets will be accepted.
Each Layer 3 switch running RIP has a route database, which contains all route entries for
reachable destination, and route table is built based on this database. When a RIP Layer 3
switch sent route update packets to its neighbor devices, the complete route table is included
in the packets. Therefore, in a large network, routing data to be transferred and processed for
each Layer 3 switch is quite large, causing degraded network performance.
Besides the above mentioned, RIP protocol allows route information discovered by the other
routing protocols to be introduced to the route table.
The operation of RIP protocol is shown below:
1． Enable RIP. The switch sends request packets to the neighbor Layer 3 switches
by broadcasting; on receiving the request, the neighbor devices reply with the
packets containing their local routing information.
2． The Layer 3 switch modifies its local route table on receiving the reply packets
and sends triggered update packets to the neighbor devices to advertise route
update information. On receiving the triggered update packet, the neighbor lay3
switches send triggered update packets to their neighbor lay3 switches. After a
sequence of triggered update packet broadcast, all Layer 3 switches get and
maintain the latest route information.
In addition, RIP Layer 3 switches will advertise its local route table to their neighbor devices
every 30 seconds. On receiving the packets, neighbor devices maintain their local route table,
select the best route and advertise the updated information to their own neighbor devices, so
that the updated routes are globally valid. Moreover, RIP uses a timeout mechanism for
outdated route, that is, if a switch does not receive regular update packets from a neighbor
within a certain interval (invalid timer interval), it considers the route from that neighbor invalid,
after holding the route fro a certain interval (holddown timer interval), it will delete that route.
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26.4.2 RIP Configuration Task List
1. Enable RIP (required)
(1) Enable/disable RIP module.
(2) Enable interface to send/receive RIP packets
2. Configure RIP protocol parameters (optional)
(1) Configure RIP sending mechanism
1) Configure specified RIP packets transmission address
2) Configure RIP interface broadcast
(2) Configure the RIP routing parameters
1) Configure route introduction (default route metric, configure routes of the other
protocols to be introduced in RIP)
2) Configure interface authentication mode and password
3) Configure the route deviation
4) Configure and apply route filter
5) Configure Split Horizon
(3) Configure other RIP protocol parameters
1) Configure the managing distance of RIP route
2) Configure the RIP route capacity limit in route table
3) Configure the RIP update, timeout, holddown and other timer.
4) Configure the receiving buffer size of RIP UDP
3. Configure RIP-I/RIP-II switch
(1) Configure the RIP version to be used in all interfaces
(2) Configure the RIP version to send/receive in all interfaces
(3) Configure whether to enable RIP packets sending/receiving for interfaces
4. Delete the specified route in RIP route table
5. Configure the RIP routing aggregation
(1) Configure aggregation route of IPv4 route mode
(2) Configure aggregation route of IPv4 interface configuration mode
(3) Display IPv4 aggregation route information
6. Configure redistribution of OSPF routing to RIP
(1) Enable Redistribution of OSPF routing to RIP
(2) Display and debug the information about configuration of redistribution of OSPF
routing to RIP
7. Configure VRF address family mode for RIP
(1) Enable/disable RIP module
(2) Configure VRF address family
1. Enable RIP protocol
Applying RIP route protocol with basic configuration in switch is simple. Normally you only
have to open the RIP switch and configure the segments running RIP, namely send and
receive the RIP data packet by default RIP configuration. The version of data packet sending
and receiving is variable when needed, allow/deny sending, receiving RIP data packet.
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Refer to 3.
Command Explanation
Global Mode
router rip
no router rip
Enables RIP; the “no router rip” command
disables RIP.
Router and Address Family Mode
network <A.B.C.D/M | ifname|vlan>
no network <A.B.C.D/M | ifname|vlan>
Enables the segment running RIP protocol; the
no network <A.B.C.D/M | ifname|vlan>
command deletes the segment.
2. Configure RIP protocol parameters
（1）Configure RIP packet transmitting mechanism
1）Configure the RIP data packet point-transmitting
2）Configure the RIP broadcast
Command Explanation
Router Mode
neighbor <A.B.C.D>
no neighbor <A.B.C.D>
Specify the IP address of the neighbor router
needs point-transmitting; the no neighbor
<A.B.C.D> command cancels the appointed
router.
passive-interface<ifname|vlan>
no passive-interface<ifname|vlan >
Block the RIP broadcast on specified pot and the
RIP data packet is only transmittable among
Layer 3 switch configured with neighbor. The no
passive-interface<ifname|vlan > command
cancels the function.
（2）Configure RIP route parameters
1）Configure route introduction (default route metric, configure routes of the other protocols to
be introduced in RIP)
Command Explanation
Router Mode
default-metric <value>
no default-metric
Sets the default route metric for route to be
introduced; the “no default-metric” command
restores the default setting.
redistribute {kernel |connected| static|
ospf | isis| bgp} [metric<value>]
[route-map<word>]
no redistribute {kernel |connected|
static| ospf | isis| bgp} [metric<value>]
[route-map<word>]
Redistribute the routes distributed in other
routing protocols into the RIP data packet; the
no redistribute {kernel |connected| static|
ospf | isis| bgp} [metric<value>]
[route-map<word>] command cancels the
distributed route of corresponding protocols.
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default-information originate
no default-information originate
Generate a default route to the RIP protocol; the
no default-information originate command
cancels the feature.
2）Configure interface authentication mode and password
Command Explanation
VLAN Interface Mode
ip rip authentication mode { text| md5}
no ip rip authentication mode [text|
md5]
Sets the authentication method; the no ip rip
authentication mode [text| md5] command
cancels the authentication action.
ip rip authentication string <text>
no ip rip authentication string
Sets the authentication key; the no ip rip
authentication string command means no key
is needed.
ip rip authentication key-chain
<name-of-chain>
no ip rip authentication key-chain
[<name-of-chain>]
Sets the key chain used in authentication, the no
ip rip authentication key-chain
[<name-of-chain>] command means the key
chain is not used.
ip rip authentication cisco-compatible
no ip rip authentication
cisco-compatible
After configure this command, configure MD5
authentication, then can receive RIP packet of
cisco, the no command restores the default
configuration.
Global Mode
key chain <name-of-chain>
no key chain < name-of-chain >
Enter keychain mode, and configure a key
chain, the no key chain < name-of-chain >
command deletes the key chain.
Keychain Mode
key <keyid>
no key <keyid>
Enter the keychain-key mode and configure a
key of the keychain; the no key <keyid>
command deletes one key.
Keychain-key Mode
key-string <text>
no key-string <text>
Configure the password used by the key, the no
key-string <text> command deletes the
password.
accept-lifetime <start-time>
{<end-time>| duration<seconds>|
infinite}
no accept-lifetime
Configure a key on the key chain and accept it
as an authorized time; the no accept-lifetime
command deletes it.
send-lifetime <start-time> {<end-time>|
duration<seconds>| infinite}
no send-lifetime
Configure the transmitting period of a key on the
key chain; the no send-lifetime command
deletes the send-lifetime.
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3）Configure the route deviation
Command Explanation
Router Mode
offset-list <access-list-number |
access-list-name> {in | out } <number>
[<ifname>]
no offset-list <access-list-number
|access-list-name> {in|out }<number
>[<ifname>]
Configure that provide a deviation value to the
route metric value when the port sends or
receives RIP data packet; the no offset-list
<access-list-number |access-list-name>
{in|out } <number >[<ifname>] command
removes the deviation table.
4）Configure and apply the route filtering
Command Explanation
Router Mode
distribute-list {< access-list-number
|access-list-name
>|prefix<prefix-list-name>}{in|out}
[<ifname>]
no distribute-list {< access-list-number
|access-list-name
>|prefix<prefix-list-name>}{in|out}
[<ifname>]
Configure and apply the access table and prefix
table to filter the routes. The no distribute-list
{< access-list-number
|access-list-name>|prefix<prefix-list-name>}{
in|out} [<ifname>]command means do not use
the access table and prefix table.
5）Configure the split horizon
Command Explanation
VLAN Interface Mode
ip rip split-horizon [poisoned]
no ip rip split-horizon
Configure that take the split horizon when the
port sends data packets; poisoned for poison
reverse the no ip rip split-horizon command
cancels the split horizon.
（3）Configure other RIP protocol parameters
1）Configure RIP routing priority
2）Configure the RIP route capacity limit in route table
3）Configure timer for RIP update, timeout and hold-down
4）Configure RIP UDP receiving buffer size
Command Explanation
Router Mode
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distance <number> [<A.B.C.D/M> ]
[<access-list-name|access-list-number
>]
no distance [<A.B.C.D/M> ]
Specify the route administratively distance of
RIP protocol; the no distance [<A.B.C.D/M> ]
command restore the default value 120.
maximum-prefix
<maximum-prefix>[<threshold>]
no maximum-prefix <maximum-prefix >
no maximum-prefix
Configure the maximum of RIP route; the no
maximum-prefix <maximum-prefix >
no maximum-prefix command cancels the
limit.
timers basic <update> <invalid>
<garbage>
no timers basic
Adjust the update, timeout and garbage
collection time, the no timers basic command
restores the default configuration.
recv-buffer-size <size>
no recv-buffer-size
The command configures the UDP receiving
buffer size of the RIP; the no recv-buffer-size
command restores the system default values.
3. Configure RIP-I/RIP-II toggling
（1）Configure the RIP version to be used in all ports
Command Explanation
RIP Mode
version { 1 | 2 }
no version
Configure the versions of all the RIP data
packets transmitted/received by the Layer 3
switch port sending/receiving the no version
command restores the default configuration,
version 2.
（2）Configure the RIP version to send/receive in all ports.
（3）Configure whether to enable RIP packets sending/receiving for ports
Command Explanation
VLAN Interface Mode
ip rip send version { 1 | 1-compatible |
2 }
no ip rip send version
Sets the version of RIP packets to send on all
ports; the no ip rip send version command set
the version to the one configured by the version
command.
ip rip receive version {1 | 2 | }
no ip rip receive version
Sets the version of RIP packets to receive on all
ports; the no action of this command set the
version to the one configured by the version
command.
ip rip receive-packet
no ip rip receive-packet
Enables receiving RIP packets on the interface;
the no ip rip receive-packet command close
data receiving on this port.
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ip rip send-packet
no ip rip send-packet
Enables sending RIP packets on the interface;
the “no ip rip send-packet” command disables
sending RIP packets on the interface.
4. Delete the specified route in RIP route table
Command Explanation
Admin Mode
clear ip rip route
{<A.B.C.D/M>|kernel|static|connected|r
ip|ospf|isis|bgp|all}
The command deletes a specified route from the
RIP route table.
5. Configure the RIP routing aggregation
（1） Configure IPv4 aggregation route globally
Command Explanation
Router Mode
ip rip aggregate-address A.B.C.D/M
no ip rip aggregate-address A.B.C.D/M
To configure or delete IPv4 aggregation route
globally.
（2） Configure IPv4 aggregation route on interface
Command Explanation
VLAN Interface Mode
ip rip aggregate-address A.B.C.D/M
no ip rip aggregate-address
A.B.C.D/M
To configure or delete IPv4 aggregation route
on interface.
（3） Display IPv4 aggregation route information
Command Explanation
Admin Mode
show ip rip aggregate To display aggregation route information.
6. Configure redistribution of OSPF routing to RIP
(1) Enable Redistribution of OSPF routing to RIP
Command Explanation
Router RIP Mode
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redistribute ospf [ <process-id> ] [metric
<value> ] [route-map <word> ]
no redistribute ospf [ <process-id> ]
To enable or disable the redistribution of
OSPF routing to RIP.
(2) Display and debug the information about configuration of redistribution of OSPF
routing to RIP
Command Explanation
Admin Mode
debug rip redistribute message send
no debug rip redistribute message send
debug rip redistribute route receive
no debug rip redistribute route receive
To enable or disable debugging messages
sent by RIP for redistribution of OSPF routing.
To enable or disable debugging messages
received from NSM.
7. Configure VRF address family mode for RIP
Command Explanation
Router RIP Mode
address-family ipv4 vrf <vrf-name>
no address-family ipv4 vrf <vrf-name>
The command configures a RIP address family
on the VRF of the PE router; the no command
deletes the configured address family.
Address Family Mode
exit-address-family This command exits the address family mode.
26.4.3 RIP Examples – Typical RIP
SWITCHA
SWITCHB
SWITCHC
Interface Interface
vlan1:10.1.1.1/24 vlan1:10.1.1.2/24
Interface
vlan2:20.1.1.1/24
Interface
vlan1:20.1.1.2/24
Figure 26-2 RIP example
In the figure shown above, a network consists of three Layer 3 switches, in which SwitchA
connected with SwitchB and SwitchC, and RIP routing protocol is running in all of the three
switches. SwitchA （interface vlan1：10.1.1.1,interface vlan2：20.1.1.1）exchanges Layer 3
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switch update messages only with SwitchB（interface vlan1：10.1.1.2）, but not with SwitchC
（interface vlan 2: 20.1.1.2）.
SwitchA, SwitchB, SwitchC configurations are as follows:
a) Layer 3 SwitchA：
Configure the IP address of interface vlan 1
SwitchA#config
SwitchA(config)# interface vlan 1
SwitchA(Config-if-Vlan1)# ip address 10.1.1.1 255.255.255.0
SwitchA(config-if-Vlan1)#
Configure the IP address of interface vlan 2
SwitchA(config)# vlan 2
SwitchA(Config-Vlan2)# switchport interface ethernet 1/0/2
Set the port Ethernet1/0/1 access vlan 2 successfully
SwitchA(Config-Vlan2)# exit
SwitchA(config)# interface vlan 2
SwitchA(Config-if-Vlan2)# ip address 20.1.1.1 255.255.255.0
Initiate RIP protocol and configure the RIP segments
SwitchA(config)#router rip
SwitchA(config-router)#network vlan 1
SwitchA(config-router)#network vlan 2
SwitchA(config-router)#exit
Configure that the interface vlan 2 do not transmit RIP messages to SwitchC
SwitchA(config)#router rip
SwitchA(config-router)#passive-interface vlan 2
SwitchA(config-router)#exit
SwitchA(config) #
b) Layer 3 SwitchB
Configure the IP address of interface vlan 1
SwitchB#config
SwitchB(config)# interface vlan 1
SwitchB(Config-if-Vlan1)# ip address 10.1.1.2 255.255.255.0
SwitchB(Config-if-Vlan1)exit
Initiate RIP protocol and configure the RIP segments
SwitchB(config)#router rip
SwitchB(config-router)#network vlan 1
SwitchB(config-router)#exit
c) Layer 3 SwitchC
Configure the IP address of interface vlan 1
SwitchC#config
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SwitchC(config)# interface vlan 1
Configure the IP address of interface vlan 1
SwitchC(Config-if-Vlan1)# ip address 20.1.1.2 255.255.255.0
SwitchC(Config-if-Vlan1)#exit
Initiate RIP protocol and configure the RIP segments
SwitchC(config)#router rip
SwitchC(config-router)#network vlan 1
SwitchC(config-router)#exit
26.4.4 RIP Examples – RIP aggregation function
The application topology as follows：
S1
S2
vlan1:192.168.10.2
vlan1:192.168.10.1
192.168.20.0/22
192.168.21.0/24
192.168.22.0/24
192.168.23.0/24
192.168.24.0/24
Figure 26-3 Typical application of RIP aggregation
As the above network topology, S2 is connected to S1 through interface vlan1, there are other
4 subnet routers of S2, which are 192.168.21.0/24, 192.168.22.0/24, 192.168.23.0/24,
192.168.24.0/24. S2 supports route aggregation, and to configure aggregation route
192.168.20.0/22 in interface vlan1 of S2, after that, sending router messages to S1 through
vlan1, and put the four subnet routers aggregated to one router as 192.168.20.0/22, and send
to S1, and not send subnet to neighbor. It can reduce the router table of S1, save the memory.
S1 configuration list:
S1(config)#router rip
S1(config-router) #network vlan 1
S2 configuration list:
S2(config)#router rip
S2(config-router) #network vlan 1
S2(config-router) #exit
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S2(config)#in vlan 1
S2(Config-if-Vlan1)# ip rip agg 192.168.20.0/22
26.4.5 RIP Troubleshooting
The RIP protocol may not be working properly due to errors such as physical connection,
configuration error when configuring and using the RIP protocol. So users should pay attention
to following:
First ensure the physic connection is correct
Second, ensure the interface and chain protocol are UP (use show interface
command)
Then initiate the RIP protocol (use router rip command) and configure the segment
(use network command) and set RIP protocol parameter on corresponding interfaces,
such as the option between RIP-I and RIP-II
After that, one feature of RIP protocol should be noticed ---the Layer 3 switch running
RIP protocol sending route updating messages to all neighboring Layer 3 switches
every 30 seconds. A Layer 3 switch is considered inaccessible if no route updating
messages from the switch is received within 180 seconds, then the route to the switch
will remains in the route table for 120 seconds before it is deleted. Therefore, if to delete
a RIP route, this route item is assured to be deleted from route table after 300 seconds.
When exchanging routing messages with CE using RIP protocol on the PE router, we
should first create corresponding VPN routing/transmitting examples to associate with
corresponding interfaces. Then enter the RIP address family mode configuring
corresponding parameters. If the RIP routing problem remains unresolved, please use
debug rip command to record the debug message in three minutes, and send them to
our technical service center.
26.5 OSPF
26.5.1 Introduction to OSPF
OSPF is abbreviation for Open Shortest Path First. It is an interior dynamic routing protocol for
autonomous system based on link-state. The protocol creates a link-state database by
exchanging link-states among Layer 3 switches, and then uses the Shortest Path First
algorithm to generate a route table basing on that database.
Autonomous system (AS) is a self-managed interconnected network. In large networks, such
as the Internet, a giant interconnected network is broken down to autonomous systems. Big
enterprise networks connecting to the Internet are independent AS, since the other hosts on
the Internet are not managed by those AS and they don’t share interior routing information with
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the Layer 3 switches on the Internet.
Each link-state Layer 3 switch can provide information about the topology with its neighboring
Layer 3 switches.
• The network segment (link) connecting to the Layer 3 switch
• State of the connecting link
Link-state information is flooded throughout the network so that all Layer 3 switches can get
firsthand information. Link-state Layer 3 switches will not broadcast all information contained in
their route tables; instead, they only send changed link-state information. Link-state Layer 3
switches establish neighborhood by sending “HELLO” to their neighbors, then link-state
advertisements (LSA) will be sent among neighboring Layer 3 switches. Neighboring Layer 3
switch copy the LSA to their routing table and transfer the information to the rest part of the
network. This process is referred to as “flooding”. In this way, firsthand information is sent
throughout the network to provide accurate map for creating and updating routes in the
network. Link-state routing protocols use cost instead of hops to decide the route. Cost is
assigned automatically or manually. According to the algorithm in link-state protocol, cost can
be used to calculate the hop number for packets to pass, link bandwidth, and current load of
the link. The administrator can even add weight for better assessment of the link-state.
1) When a link-state Layer 3 switch enters a link-state interconnected network, it sends a
HELLO packet to get to know its neighbors and establish neighborhood.
2) The neighbors respond with information about the links they are connecting and the
related costs.
3) The originate Layer 3 switch uses this information to build its own routing table
4) Then, as part of the regular update, Layer 3 switch send link-state advertisement (LSA)
packets to its neighboring Layer 3 switches. The LSA include links and related costs of
that Layer 3 switch.
5) Each neighboring Layer 3 switch copies the LSA packet and passes it to the next
neighbor (i.e. flooding).
6) Since routing database is not recalculated before Layer 3 switch forwards LSA flooding,
the converging time is greatly reduced.
One major advantage of link-state routing protocols is the fact that infinite counting is
impossible, this is because of the way link-state routing protocols build up their routing table.
The second advantage is that converging in a link-state interconnected network is very fast,
once the routing topology changes, updates will be flooded throughout the network very soon.
Those advantages release some Layer 3 switch resources, as the process ability and
bandwidth used by bad route information are minor.
The features of OSPF protocol include the following: OSPF supports networks of various
scales, several hundreds of Layer 3 switches can be supported in an OSPF network. Routing
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topology changes can be quickly found and updating LSAs can be sent immediately, so that
routes converge quickly. Link-state information is used in shortest path algorithm for route
calculation, eliminating loop route. OSPF divides the autonomous system into areas, reducing
database size, bandwidth occupation and calculation load. (According to the position of Layer
3 switches in the autonomous system, they can be grouped as internal area switches, area
border switches, AS border switches and backbone switches). OSPF supports load balance
and multiple routes to the same destination of equal costs. OSPF supports 4 level routing
mechanisms (process routing according to the order of intra-area path, inter-area path, type 1
external path and type 2 external path). OSPF supports IP subnet and redistribution of routes
from the other routing protocols, and interface-based packet verification. OSPF supports
sending packets in multicast.
Each OSPF Layer 3 switch maintains a database describing the topology of the whole
autonomous system. Each Layer 3 switch gathers the local status information, such as
available interface, reachable neighbors, and sends link-state advertisement (sending out
link-state information) to exchange link-state information with other OSPF Layer 3 switches to
form a link-state database describing the whole autonomous system. Each Layer 3 switch
builds a shortest path tree rooted by itself according to the link-state database, this tree
provides the routes to all nodes in an autonomous system. If two or more Layer 3 switches
exist (i.e. multi-access network), "designated Layer 3 switch” and “backup designated Layer 3
switch” will be selected. Designated Layer 3 switch is responsible for spreading link-state of
the network. This concept helps reducing the traffic among the Layer 3 switches in
multi-access network.
OSPF protocol requires the autonomous system to be divided into areas. That is to divide the
autonomous system into 0 area (backbone area) and non-0 areas. Routing information
between areas are further abstracted and summarized to reduce the bandwidth required in the
network. OSPF uses four different kinds of routes; they are intra-area route, inter-area route,
type 1 external route and type 2 external route, in the order of highest priority to lowest. The
route inside an area and between areas describes the internal network structure of an
autonomous system, while external routes describe how to select the routing information to
destination outside the autonomous system. The first type of exterior route corresponds to the
information introduced by OSPF from the other interior routing protocols, the costs of those
routes are comparable with the costs of OSPF routes; the second type of exterior route
corresponds to the information introduced by OSPF from the other exterior routing protocols,
but the costs of those routes are far greater than that of OSPF routes, so OSPF route cost is
ignored when calculating route costs.
OSPF areas are centered with the Backbone area, identified as Area 0, all the other areas
must be connected to Area 0 logically, and Area 0 must be continuous. For this reason, the
concept of virtual link is introduced to the backbone area, so that physically separated areas
still have logical connectivity to the backbone area. The configurations of all the Layer 3
switches in the same area must be the same.
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In conclusion, LSA can only be transferred between neighboring Layer 3 switches, OSPF
protocol includes 5 types of LSA: router LSA, network LSA, network summary LSA to the other
areas, ASBR summary LSA and AS external LSA. They can also be called type1 LSA, type2
LSA, type3 LSA, type4 LSA, and type5 LSA. Router LSA is generated by each Layer 3 switch
inside an OSPF area, and is sent to all the other neighboring Layer 3 switches in the same
area; network LSA is generated by the designated Layer 3 switch in the OSPF area of
multi-access network, and is sent to all other neighboring Layer 3 switches in this area. (In
order to reduce traffic on Layer 3 switches in the multi-access network, “designated Layer 3
switch” and “backup designated Layer 3 switch” should be selected in the multi-access
network, and the network link-state is broadcasted by the designated Layer 3 switch); network
summary LSA is generated by border switches in an OSPF area , and is transferred among
area border Layer 3 switches; AS external LSA is generated by Layer 3 switches on external
border of AS, and is transferred throughout the AS.
As to autonomous systems mainly advertises exterior link-state, OSPF allow some areas to be
configured as STUB areas to reduce the size of the topology database. Type4 LSA (ASBR
summary LSA) and type5 LSA (AS external LSA) are not allowed to flood into/through STUB
areas. STUB areas must use the default routes, the Layer 3 switches on STUB area edge
advertise the default routes to STUB areas by type 3 summary LSA, those default routes only
floods inside STUB area and will not get out of STUB area. Each STUB area has a
corresponding default route, the route from a STUB area to AS exterior destination must rely
on the default route of that area.
The following simply outlines the route calculation process of OSPF protocol:
1） Each OSPF-enabled Layer 3 switch maintains a database (LS database) describing
the link-state of the topology structure of the whole autonomous system. Each Layer
3 switch generates a link-state advertisement according to its surrounding network
topology structure (router LSA), and sends the LSA to other Layer 3 switches through
link-state update (LSU) packets. Thus each Layer 3 switches receives LSAs from
other Layer 3 switches, and all LSAs are combined to the link-state database.
2） Since a LSA is the description of the network topology structure around a Layer 3
switch, the LS database is the description of the network topology structure of the
whole network. The Layer 3 switches can easily create a weighted vector map
according to the LS database. Obviously, all Layer 3 switches in the same
autonomous system will have the same network topology map.
3） Each Layer 3 switch uses the shortest path first (SPF) algorithm to calculate a tree of
shortest path rooted by itself. The tree provides the route to all the nodes in the
autonomous system, leaf nodes consist of the exterior route information. The exterior
route can be marked by the Layer 3 switch broadcast it, so that additional information
about the autonomous system can be recorded. As a result, the route table of each
Layer 3 switch is different.
OSPF protocol is developed by the IETF, the OSPF v2 widely used now is fulfilled according to
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the content described in RFC2328.
26.5.2 OSPF Configuration Task List
The OSPF configuration for SGS-6340 series switches may be different from the configuration
procedure to switches of the other manufacturers. It is a two-step process:
Enable OSPF in the Global Mode;2, Configure OSPF area for the interfaces. The configuration
task list is as follows:
1. Enable OSPF protocol (required)
(1) Enable/disable OSPF protocol (required)
(2) Configure the ID number of the Layer 3 switch running OSPF (optional)
(3) Configure the network scope for running OSPF (optional)
(4) Configure the area for the interface (required)
2. Configure OSPF protocol parameters (optional)
(1) Configure OSPF packet sending mechanism parameters
1) Configure OSPF packet verification
2) Set the OSPF interface to receive only
3) Configure the cost for sending packets from the interface
4) Configure OSPF packet sending timer parameter (timer of broadcast interface
sending HELLO packet to poll, timer of neighboring Layer 3 switch invalid
timeout, timer of LSA transmission delay and timer of LSA retransmission.
(2) Configure OSPF route introduction parameters
1) Configure default parameters (default type, default tag value, default cost)
2) Configure the routes of the other protocols to introduce to OSPF.
(3) Configure OSPF importing the routes of other OSPF processes
1) Enable the function of OSPF importing the routes of other OSPF processes
2) Display relative information
3) Debug
(4) Configure other OSPF protocol parameters
1) Configure OSPF routing protocol priority
2) Configure cost for OSPF STUB area and default route
3) Configure OSPF virtual link
4) Configure the priority of the interface when electing designated Layer 3 switch
(DR).
5) Configure to keep a log for OSPF adjacency changes or not
3. Disable OSPF protocol
1. Enable OSPF protocol
Basic configuration of OSPF routing protocol on switch is quite simple, usually only enabling
OSPF and configuration of the OSPF area for the interface are required. The OSPF protocol
parameters can use the default settings. If OSPF protocol parameters need to be modified,
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please refer to “2. Configure OSPF protocol parameters”.
Command Explanation
Global Mode
[no] router ospf [process <id>]
Enables OSPF protocol; the “no router
ospf” command disables OSPF protocol.
(required)
OSPF Protocol Configuration Mode
router-id <router_id>
no router-id
Configures the ID number for the Layer 3
switch running OSPF; the “no router id”
command cancels the ID number. The IP
address of an interface is selected to be the
Layer 3 switch ID. (optional)
[no] network {<network> <mask> |
<network>/<prefix>} area <area_id>
Configure certain segment to certain area,
the no [no] network {<network> <mask> |
<network>/<prefix>} area <area_id>
command cancels this configuration.
(required)
2. Configure OSPF protocol parameters
（1）Configure OSPF packet sending mechanism parameters
1）Configure OSPF packet verification
2）Set the OSPF interface to receive only
3）Configure the cost for sending packets from the interface
Command Explanation
Interface Configuration Mode
ip ospf authentication
{ message-digest | null}
no ip ospf authentication
Configures the authentication method by the
interface to accept OSPF packets; the no ip
ospf authentication command restores the
default settings.
ip ospf authentication-key LINE
no ip ospf authentication-key
Configure the key of the authentication process
of OSPF data packets receiving for the
interfaces; the no action of this command
restores the default settings.
ip ospf cost <cost >
no ip ospf cost
Sets the cost for running OSPF on the interface;
the no ip ospf cost command restores the
default setting.
4）Configure OSPF packet sending timer parameter (timer of broadcast interface sending
HELLO packet to poll, timer of neighboring Layer 3 switch invalid timeout, timer of LSA
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transmission delay and timer of LSA retransmission.
Command Explanation
Interface Configuration Mode
ip ospf hello-interval <time>
no ip ospf hello-interval
Sets interval for sending HELLO packets; the
“no ip ospf hello-interval” command restores
the default setting.
ip ospf dead-interval <time >
no ip ospf dead-interval
Sets the interval before regarding a neighbor
Layer 3 switch invalid; the “no ip ospf
dead-interval” command restores the default
setting.
ip ospf transit-delay <time>
no ip ospf transit-delay
Sets the delay time before sending link-state
broadcast; the “no ip ospf transmit-delay”
command restores the default setting.
ip ospf retransmit-interval <time>
no ip ospf retransmit-interval
Sets the interval for retransmission of link-state
advertisement among neighbor Layer 3
switches; the “no ip ospf retransmit-interval”
command restores the default setting.
（2）Configure OSPF route introduction parameters
Configure the routes of the other protocols to introduce to OSPF.
Command Explanation
OSPF Protocol Configuration Mode
redistribute { bgp | connected | static |
rip | kernel} [ metric-type { 1 | 2 } ] [ tag
<tag> ] [ metric <cost_value> ]
[router-map <WORD>]
no redistribute { bgp | connected |
static | rip | kernel }
Distribute other protocols to find routing and
static routings as external routing messages
the no redistribute {bgp | connected |
static | rip | kernel} command cancels the
distributed external messages.
（3）Configure OSPF importing the routes of other OSPF processes
1）Enable the function of OSPF importing the routes of other OSPF processes
Command Explanation
Router OSPF Mode
redistribute ospf [<process-id>]
[metric<value>] [metric-type
{1|2}][route-map<word>]
no redistribute ospf [<process-id>]
[metric<value>] [metric-type
{1|2}][route-map<word>]
Enable or disable the function of OSPF
importing the routes of other OSPF
processes.
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2）Display relative information
Command Explanation
Admin Mode or Configure Mode
show ip ospf [<process-id>]
redistribute
Display the configuration information of the
OSPF process importing other outside
routes.
3）Debug
Command Explanation
Admin Mode
debug ospf redistribute message send
no debug ospf redistribute message
send
debug ospf redistribute route receive
no debug ospf redistribute route
receive
Enable or disable debugging of sending
command from OSPF process redistributed
to other OSPF process routing.
Enable or disable debugging of received
routing message from NSM for OSPF
process.
（4）Configure other OSPF protocol parameters
1）Configure how to calculate OSPF SPF algorithm time
2）Configure the LSA limit in the OSPF link state database
3）Configure various OSPF parameters
Command Explanation
OSPF Protocol Configuration Mode
timers spf <interval>
no timers spf
Configure the SPF timer of OSPF; the
no timers spf command restores the
default settings.
overflow database {<max-LSA> [hard | soft]
| external <max-LSA> <recover time>}
no overflow database [external <max-LSA
> < recover time >]
Configure the LSA limit in current OSPF
process database; the no overflow
database [external < max-LSA > <
recover time >] command restores the
default settings.
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area <id> {authentication [message-digest]
| default-cost <cost> | filter-list {access |
prefix} <WORD> {in | out} | nssa
[default-information-originate |
no-redistribution | no-summary |
translator-role] | range <range> | stub
[no-summary] | virtual-link <neighbor>}
no area <id> {authentication | default-cost |
filter-list {access | prefix} <WORD> {in |
out} | nssa [default-information-originate |
no-redistribution | no-summary |
translator-role] | range <range> | stub
[no-summary] | virtual-link <neighbor>}
Configure the parameters in OSPF area
(STUB area, NSSA area and virtual
links); the no area <id> {authentication
| default-cost | filter-list {access |
prefix} <WORD> {in | out} | nssa
[default-information-originate |
no-redistribution | no-summary |
translator-role] | range <range> | stub
[no-summary] | virtual-link
<neighbor>} command restores the
default settings.
4）Configure the priority of the interface when electing designated Layer 3 switch (DR).
Command Explanation
Interface Configuration Mode
ip ospf priority <priority>
no ip ospf priority
Sets the priority of the interface in “designated
Layer 3 switch” election; the no ip ospf priority
command restores the default setting.
5）Configure to keep a log for OSPF adjacency changes or not
Command Explanation
OSPF Protocol Configuration Mode
log-adjacency-changes detail
no log-adjacency-changes detail
Configure to keep a log for OSPF adjacency
changes or not.
5）Filter the route obtained by OSPF
Command Explanation
OSPF Protocol Configuration Mode
filter-policy <access-list-name>
no filter-policy
Use access list to filter the route obtained by
OSPF, the no command cancels the route
filtering.
3. Disable OSPF protocol
Command Explanation
Global Mode
no router ospf [process <id>] Disables OSPF routing protocol.
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26.5.3 OSPF Examples
26.5.4 Configuration Example of OSPF
Scenario 1: OSPF autonomous system.
This scenario takes an OSPF autonomous system consists of five switch for example.
Switch A
Switch B
Switch E Switch D
Switch C
E1/2:10.1.1.1
vlan1
E1/1:10.1.1.2
vlan1
E1/1:100.1.1.1
vlan2
E1/1:100.1.1.2
vlan2
E1/2:20.1.1.1
vlan3
E1/1:20.1.1.2
vlan3
E1/2:30.1.1.1
vlan3
E1/1:30.1.1.2
vlan3
Area 1
Area 0
Figure 26-4 Network topology of OSPF autonomous system
The configuration for Layer 3 Switch1 and Switch5 is shown below:
Layer 3 Switch1
Configuration of the IP address for interface vlan1
Switch1#config
Switch1(config)# interface vlan 1
Switch1(config-if-vlan1)# ip address 10.1.1.1 255.255.255.0
Switch1(config-if-vlan1)#exit
Configuration of the IP address for interface vlan2
Configure the IP address of interface vlan2
Switch1(config)# interface vlan 2
Switch1(config-if-vlan2)# ip address 100.1.1.1 255.255.255.0
Switch1 (config-if-vlan2)#exit
Enable OSPF protocol, configure the area number for interface vlan1 and vlan2.
Switch1(config)#router ospf
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Switch1(config-router)#network 10.1.1.0/24 area 0
Switch1(config-router)#network 100.1.1.0/24 area 0
Switch1(config-router)#exit
Switch1(config)#exit
Switch1#
Layer 3 Switch2:
Configure the IP address for interface vlan1 and vlan2.
Switch2#config
Switch2(config)# interface vlan 1
Switch2(config-if-vlan1)# ip address 10.1.1.2 255.255.255.0
Switch2(config-if-vlan1)#no shutdown
Switch2(config-if-vlan1)#exit
Switch2(config)# interface vlan 3
Switch2(config-if-vlan3)# ip address 20.1.1.1 255.255.255.0
Switch2(config-if-vlan3)#no shutdown
Switch2(config-if-vlan3)#exit
Enable OSPF protocol, configure the OSPF area interfaces vlan1 and vlan3 in
Switch2(config)#router ospf
Switch2(config-router)# network 10.1.1.0/24 area 0
Switch2(config-router)# network 20.1.1.0/24 area 1
Switch2(config-router)#exit
Switch2(config)#exit
Switch2#
Layer 3 Switch3:
Configuration of the IP address for interface vlan3.
Switch3#config
Switch3(config)# interface vlan 3
Switch3(config-if-vlan1)# ip address 20.1.1.2 255.255.255.0
Switch3(config-if-vlan3)#no shutdown
Switch3(config-if-vlan3)#exit
Initiate the OSPF protocol, configure the OSPF area to which interface vlan3 belongs
Switch3(config)#router ospf
Switch3(config-router)# network 20.1.1.0/24 area 1
Switch3(config-router)#exit
Switch3(config)#exit
Switch3#
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Layer 3 Switch4:
Configuration of the IP address for interface vlan3
Switch4#config
Switch4(config)# interface vlan 3
Switch4(config-if-vlan3)# ip address30.1.1.2 255.255.255.0
Switch4(config-if-vlan3)#no shutdown
Switch4(config-if-vlan3)#exit
Enable OSPF protocol, configure the OSPF area interfaces vlan3 resides in.
Switch4(config)#router ospf
Switch4(config-router)# network 30.1.1.0/24 area 0
Switch4(config-router)#exit
Switch4(config)#exit
Switch4#
Layer 3 Switch5:
Configuration of the IP address for interface vlan2
Switch5#config
Switch5(config)# interface vlan 2
Switch5(config-if-vlan2)# ip address 100.1.1.2 255.255.255.0
Switch5(config-if-vlan2)#no shutdown
Switch5(config-if-vlan2)#exit
Configuration of the IP address for interface vlan3
Switch5(config)# interface vlan 3
Switch5(config-if-vlan3)# ip address 30.1.1.1 255.255.255.0
Switch5(config-if-vlan3)#no shutdown
Switch5(config-if-vlan3)#exit
Enable OSPF protocol, configure the number of the area in which interface vlan2 and vlan3
reside in.
Switch5(config)#router ospf
Switch5(config-router)# network 30.1.1.0/24 area 0
Switch5(config-router)# network 100.1.1.0/24 area 0
Switch5(config-router)#exit
Switch5(config)#exit
Switch5#
Scenario 2: Typical OSPF protocol complex topology.
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Area 3
Area 2
Area 1
N3
N1
N8
N5
N6 N9
N10
N4
N2
N15 N14
N7
N11
Area 0
N12N13
Switch H
Switch G
Switch J
Switch K
Switch L
Switch I
Switch F
Switch E
Switch D
Switch C
Switch B
Switch A
Figure 26-5 Typical complex OSPF autonomous system
This scenario is a typical complex OSPF autonomous system network topology. Area1 include
network N1-N4 and Layer 3 SwitchA-SwitchD, area2 include network N8-N10, host H1 and
Layer 3 SwitchH, area3 include N5-N7 and Layer 3 SwitchF, SwitchG SwitchA0 and Switch11,
and network N8-N10 share a summary route with host H1(i.e. area3 is defined as a STUB
area). Layer 3 SwitchA, SwitchB, SwitchD, SwitchE, SwitchG, SwitchH, Switch12 are in-area
Layer 3 switches, SwitchC, SwitchD, SwitchF, Switch10 and Switch11 are edge Layer 3
switches of the area, SwitchD and SwitchF are edge Layer 3 switches of the autonomous
system.
To area1, Layer 3 switches SwitchA and SwitchB are both in-area switches, area edge
switches SwitchC and SwitchD are responsible for reporting distance cost to all destination
outside the area, while they are also responsible for reporting the position of the AS edge
Layer 3 switches SwitchD and SwitchF, AS exterior link-state advertisement from SwitchD and
SwitchF are flooded throughout the whole autonomous system. When ASE LSA floods in area
1, those LSAs are included in the area 1 database to get the routes to network N11 and N15.
In addition, Layer 3 SwitchC and SwitchD must summary the topology of area 1 to the
backbone area (area 0, all non-0 areas must be connected via area 0, direct connections are
not allowed), and advertise the networks in area 1 (N1-N4) and the costs from SwitchC and
SwitchD to those networks. As the backbone area is required to keep connected, there must
be a virtual link between backbone Layer 3 Switch10 and Switch11. The area edge Layer 3
switches exchange summary information via the backbone Layer 3 switch, each area edge
Layer 3 switch listens to the summary information from the other edge Layer 3 switches.
Virtual link can not only maintain the connectivity of the backbone area, but also strengthen the
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backbone area. For example, if the connection between backbone Layer 3 SwitchG and
Switch10 is cut down, the backbone area will become incontinuous. The backbone area can
become more robust by establishing a virtual link between backbone Layer 3 switches SwitchF
and Switch10. In addition, the virtual link between SwitchF and Switch10 provide a short path
from area 3 to Layer 3 Switch F.
Take area 1 as an example. Assume the IP address of Layer 3 SwitchA is 10.1.1.1, IP address
of Layer 3 Switch B interface VLAN2 is 10.1.1.2, IP address of Layer 3 SwitchC interface
VLAN2 is 10.1.1.3, IP address of Layer 3 SwitchD interface VLAN2 is 10.1.1.4. SwitchA is
connecting to network N1 through Ethernet interface VLAN1 (IP address 20.1.1.1); SwitchB is
connecting to network N2 through Ethernet interface VLAN1 (IP address 20.1.2.1); SwitchC is
connecting to network N4 through Ethernet interface VLAN3 (IP address 20.1.3.1). All the
three addresses belong to area 1. SwitchC is connecting to Layer 3 SwitchE through Ethernet
interface VLAN1 (IP address 10.1.5.1); SwitchD is connecting to Layer 3 SwitchD through
Ethernet interface VLAN1 (IP address 10.1.6.1); both two addresses belong to area 1. Simple
authentication is implemented among Layer 3 switches in area1, edge Layer 3 switches of
area 1 authenticate with the area 0 backbone Layer 3 switches by MD5 authentication.
The followings are just configurations for all Layer 3 switches in area 1, configurations for
Layer 3 switches of the other areas are omitted. The following are the configurations of
SwitchA, SwitchB, SwitchC and SwitchD:
1)Switch A:
Configure IP address for interface vlan2
SwitchA#config
SwitchA(config)# interface vlan 2
SwitchA(config-If-Vlan2)# ip address 10.1.1.1 255.255.255.0
SwitchA(config-If-Vlan2)#exit
Enable OSPF protocol, configure the area number for interface vlan2.
SwitchA(config)#router ospf
SwitchA(config-router)#network 10.1.1.0/24 area 1
SwitchA(config-router)#exit
Configure simple key authentication.
SwitchA(config)#interface vlan 2
SwitchA(config-If-Vlan2)#ip ospf authentication
SwitchA(config-If-Vlan2)#ip ospf authentication-key DCS
SwitchA(config-If-Vlan2)exit
Configure IP address and area number for interface vlan1.
26-40
SwitchA(config)# interface vlan 1
SwitchA(config-If-Vlan1)#ip address 20.1.1.1 255.255.255.0
SwitchA(config-If-Vlan1)#exit
SwitchA(config)#router ospf
SwitchA(config-router)#network 20.1.1.0/24 area 1
SwitchA(config-router)#exit
2)Switch B:
Configure IP address for interface vlan2
SwitchB#config
SwitchB(config)# interface vlan 2
SwitchB(config-If-Vlan2)# ip address 10.1.1.2 255.255.255.0
SwitchB(config-If-Vlan2)#exit
Enable OSPF protocol, configure the area number for interface vlan2.
SwitchB(config)#router ospf
SwitchB(config-router)#network 10.1.1.0/24 area 1
SwitchB(config-router)#exit
SwitchB(config)#interface vlan 2
Configure simple key authentication.
SwitchB(config)#interface vlan 2
SwitchB(config-If-Vlan2)#ip ospf authentication
SwitchB(config-If-Vlan2)#ip ospf authentication-key DCS
SwitchB(config-If-Vlan2)#exit
Configure IP address and area number for interface vlan1.
SwitchB(config)# interface vlan 1
SwitchB(config-If-Vlan1)#ip address 20.1.2.1 255.255.255.0
SwitchB(config-If-Vlan1)#exit
SwitchB(config)#router ospf
SwitchB(config-router)#network 20.1.2.0/24 area 1
SwitchB(config-router)#exit
SwitchB(config)#exit
3)Switch C:
Configure IP address for interface vlan2
SwitchC#config
SwitchC(config)# interface vlan 2
SwitchC(config-If-Vlan2)# ip address 10.1.1.3 255.255.255.0
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SwitchC(config-If-Vlan2)#exit
Enable OSPF protocol, configure the area number for interface vlan2
SwitchC(config)#router ospf
SwitchC(config-router)#network 10.1.1.0/24 area 1
SwitchC(config-router)#exit
Configure simple key authentication
SwitchC(config)#interface vlan 2
SwitchC(config-If-Vlan2)#ip ospf authentication
SwitchC(config-If-Vlan2)#ip ospf authentication-key DCS
SwitchC(config-If-Vlan2)#exit
Configure IP address and area number for interface vlan3
SwitchC(config)# interface vlan 3
SwitchC(config-If-Vlan3)#ip address 20.1.3.1 255.255.255.0
SwitchC(config-If-Vlan3)#exit
SwitchC(config)#router ospf
SwitchC(config-router)#network 20.1.3.0/24 area 1
SwitchC(config-router)#exit
Configure IP address and area number for interface VLAN 1
SwitchC(config)# interface vlan 1
SwitchC(config-If-Vlan1)#ip address 10.1.5.1 255.255.255.0
SwitchC(config-If-Vlan1)#exit
SwitchC(config)#router ospf
SwitchC(config-router)#network 10.1.5.0/24 area 0
SwitchC(config-router)#exit
Configure MD5 key authentication.
SwitchC(config)#interface vlan 1
SwitchC (config-If-Vlan1)#ip ospf authentication message-digest
SwitchC (config-If-Vlan1)#ip ospf authentication-key DCS
SwitchC (config-If-Vlan1)#exit
SwitchC(config)#exit
SwitchC#
4)Switch D:
Configure IP address for interface VLAN2
SwitchD#config
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SwitchD(config)# interface vlan 2
SwitchD(config-If-Vlan2)# ip address 10.1.1.4 255.255.255.0
SwitchD(config-If-Vlan2)#exit
Enable OSPF protocol, configure the area number for interface VLAN2.
SwitchD(config)#router ospf
SwitchD(config-router)#network 10.1.1.0/24 area 1
SwitchD(config-router)#exit
Configure simple key authentication.
SwitchD(config)#interface vlan 2
SwitchD(config-If-Vlan2)#ip ospf authentication
SwitchD(config-If-Vlan2)#ip ospf authentication-key DCS
SwitchD(config-If-Vlan2)#exit
Configure the IP address and the area number for the interface VLAN 1
SwitchD(config)# interface vlan 1
SwitchD(config-If-Vlan1)# ip address 10.1.6.1 255.255.255.0
SwitchD(config-If-Vlan1)exit
SwitchD(config)#router ospf
SwitchD(config-router)#network 10.1.6.0/24 area 0
SwitchD(config-router)#exit
Configure MD5 key authentication
SwitchD(config)#interface vlan 1
SwitchD(config-If-Vlan1)#ip ospf authentication message-digest
SwitchD(config-If-Vlan1)#ip ospf authentication-key DCS
SwitchD(config-If-Vlan1)exit
SwitchD(config)#exit
SwitchD#
Scenario 3: The function of OSPF importing the routers of other OSPF processes
As shown in the following graph, a switch running the OSPF routing protocol connects two
networks: network A and network B. Because of some reason, it is required that network A
should be able to learn the routers of network B, but network B should not be able to learn the
routers of network A. According to that, two OSPF processes can be started respectively on
interface VLAN 1 and interface VLAN 2. the OSPF process which interface VLAN 1 belongs to
is configured to import the routers of the OSPF process which interface VLAN 2 belongs to,
while the OSPF process which interface VLAN 2 belongs to should not be configured to import
the routers of the OSPF process which interface VLAN 1 belongs to.
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Network A
Vlan1
1.1.1.1
Vlan2
2.2.2.2 Network B
Figure 26-6 Function of OSPF importing the routers of other OSPF processes example
We can configure as follows:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 1.1.1.1 255.255.255.0
Switch(Config-if-Vlan1)#exit
Switch(config)#interface vlan 2
Switch(Config-if-Vlan2)#ip address 2.2.2.2 255.255.255.0
Switch(Config-if-Vlan2)#exit
Switch(config)#router ospf 10
Switch(config-router)#network 2.2.2.0/24 area 1
Switch(config-router)#exit
Switch(config)#router ospf 20
Switch(config-router)#network 1.1.1.0/24 area 1
Switch(config-router)#redistribute ospf 10
Switch(config-router)#exit
26.5.5 Configuration Examples of OSPF VPN
SWITCHA
SWITCHB Interface Interface
vlan1:10.1.1.1/24 vlan1:10.1.1.2/24
SWITCHC
Interface Interface
vlan2:20.1.1.1/24 vlan1:20.1.1.2/24
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Figure 26-7 OSPF VPN Example
The above figure shows that a network consists of three Layer 3 switches in which the switchA
as PE, SwitchB and SwitchC as CE1 and CE2. The PE is connected to CE1 and CE2 through
VLAN1 and VLAN2. The routing messages are exchanged between PE and CE through OSPF
protocol.
a) SwitchA, the Layer 3 switch as PE
Configure VPN route/transmitting examples vpnb and vpnc
SwitchA#config
SwitchA(config)#ip vrf vpnb
SwitchA(config-vrf)#
SwitchA(config-vrf)#exit
SwitchA#(config)
SwitchA(config)#ip vrf vpnc
SwitchA(config-vrf)#
SwitchA(config-vrf)#exit
Associate the VLAN 1 and VLAN 2 respectively with vpnb and vpnc while configuring IP
address
SwitchA(config)#in vlan1
SwitchA(config-if-Vlan1)#ip vrf forwarding vpnb
SwitchA(config-if-Vlan1)#ip address 10.1.1.1 255.255.255.0
SwitchA(config-if-Vlan1)#exit
SwitchA(config)#in vlan2
SwitchA(config-if-Vlan2)#ip vrf forwarding vpnc
SwitchA(config-if-Vlan2)#ip address 20.1.1.1 255.255.255.0
SwitchA(config-if-Vlan2)#exit
Configure OSPF examples associated with vpnb and vpnc respectively
SwitchA(config)#
SwitchA(config)#router ospf 100 vpnb
SwitchA(config-router)#network 10.1.1.0/24 area 0
SwitchA(config-router)#redistribute bgp
SwitchA(config-router)#exit
SwitchA(config)#router ospf 200 vpnc
SwitchA(config-router)#network 20.1.1.0/24 area 0
SwitchA(config-router)#redistribute bgp
b) The Layer 3 SwitchB of CE1：
Configure the IP address of Ethernet E 1/0/2
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SwitchB#config
SwitchB(config)# interface Vlan1
SwitchB(config-if-vlan1)# ip address 10.1.1.2 255.255.255.0
SwitchB (config-if-vlan1)exit
Enable OSPF protocol and configuring OSPF segments
SwitchB(config)#router ospf
SwitchB(config-router-rip)#network 10.1.1.0/24 area 0
SwitchB(config-router-rip)#exit
c) The Layer 3 SwitchC of CE2
Configure the IP address of Ethernet E 1/0/2
SwitchC#config
SwitchC(config)# interface Vlan1
SwitchC(config-if-vlan1)# ip address 20.1.1.2 255.255.255.0
SwitchC(config-if-vlan1)#exit
Initiate OSPF protocol and configuring OSPF segments
SwitchC(config)#router ospf
SwitchC(config-router)#network 20.1.1.0/24 area 0
SwitchC(config-router)#exit
26.5.6 OSPF Troubleshooting
The OSPF protocol may not be working properly due to errors such as physic connection,
configuration error when configuring and using the OSPF protocol. So users should pay
attention to following:
First ensure the physic connection is correct
Second, ensure the interface and link protocol are UP (use show interface command)
Configure different IP address from different segment on each interface
Then initiate OSPF protocol (use router-ospf command) and configure the OSPF area
on corresponding interface
After that, a OSPF protocol feature should be checked---the OSPF backbone area should be
continuous and apply virtual link to ensure it is continuous. if not; all non 0 areas should only
be connected to other non 0 area through 0 area; a border Layer 3 switch means that one part
of the interfaces of this switch belongs to 0 area, the other part belongs to non 0 area; Layer 3
switch DR should be specified for multi-access network such as broadcast network.
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26.6 ARP
26.6.1 Introduction to ARP
ARP (Address Resolution Protocol) is mainly used to resolve IP address to Ethernet MAC
address. Switch supports static ARP configuration.
26.6.2 ARP Configuration Task List
ARP Configuration Task List:
1. Configure static ARP
1. Configure static ARP
Command Explanation
VLAN Interface Mode
arp <ip_address> <mac_address>
no arp <ip_address>
Configures a static ARP entry; the no
command deletes a static ARP entry.
26.6.3 ARP Troubleshooting
If ping from the switch to directly connected network devices fails, the following can be used to
check the possible cause and create a solution.
Check whether the corresponding ARP has been learned by the switch.
If ARP has not been learned, then enabled ARP debugging information and view
the sending/receiving condition of ARP packets.
Defective cable is a common cause of ARP problems and may disable ARP
learning.
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Chapter 27 ARP Scanning Prevention
Function Configuration
27.1 Introduction to ARP Scanning Prevention
Function
ARP scanning is a common method of network attack. In order to detect all the active hosts in
a network segment, the attack source will broadcast lots of ARP messages in the segment,
which will take up a large part of the bandwidth of the network. It might even do
large-traffic-attack in the network via fake ARP messages to collapse of the network by
exhausting the bandwidth. Usually ARP scanning is just a preface of other more dangerous
attack methods, such as automatic virus infection or the ensuing port scanning, vulnerability
scanning aiming at stealing information, distorted message attack, and DOS attack, etc.
Since ARP scanning threatens the security and stability of the network with great danger, so it
is very significant to prevent it. Switch provides a complete resolution to prevent ARP scanning:
if there is any host or port with ARP scanning features is found in the segment, the switch will
cut off the attack source to ensure the security of the network.
There are two methods to prevent ARP scanning: port-based and IP-based. The port-based
ARP scanning will count the number to ARP messages received from a port in a certain time
range, if the number is larger than a preset threshold, this port will be “down”. The IP-based
ARP scanning will count the number to ARP messages received from an IP in the segment in a
certain time range, if the number is larger than a preset threshold, any traffic from this IP will be
blocked, while the port related with this IP will not be “down”. These two methods can be
enabled simultaneously. After a port or an IP is disabled, users can recover its state via
automatic recovery function.
To improve the effect of the switch, users can configure trusted ports and IP, the ARP
messages from which will not be checked by the switch. Thus the load of the switch can be
effectively decreased.
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27.2 ARP Scanning Prevention Configuration Task
Sequence
1. Enable the ARP Scanning Prevention function.
2. Configure the threshold of the port-based and IP-based ARP Scanning Prevention
3. Configure trusted ports
4. Configure trusted IP
5. Configure automatic recovery time
6. Display relative information of debug information and ARP scanning
1. Enable the ARP Scanning Prevention function.
Command Explanation
Global Mode
anti-arpscan enable
no anti-arpscan enable
Enable or disable the ARP Scanning
Prevention function globally.
2. Configure the threshold of the port-based and IP-based ARP Scanning Prevention
Command Explanation
Global Mode
anti-arpscan port-based threshold
<threshold-value>
no anti-arpscan port-based
threshold
Set the threshold of the port-based
ARP Scanning Prevention.
anti-arpscan ip-based threshold
<threshold-value>
no anti-arpscan ip-based threshold
Set the threshold of the IP-based ARP
Scanning Prevention.
3. Configure trusted ports
Command Explanation
Port Mode
anti-arpscan trust <port |
supertrust-port>
no anti-arpscan trust <port |
supertrust-port>
Set the trust attributes of the ports.
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4. Configure trusted IP
Command Explanation
Global Mode
anti-arpscan trust ip <ip-address>
[<netmask>]
no anti-arpscan trust ip <ip-address>
[<netmask>]
Set the trust attributes of IP.
5. Configure automatic recovery time
Command Explanation
Global Mode
anti-arpscan recovery enable
no anti-arpscan recovery enable
Enable or disable the automatic
recovery function.
anti-arpscan recovery time <seconds>
no anti-arpscan recovery time Set automatic recovery time.
6. Display relative information of debug information and ARP scanning
Command Explanation
Global Mode
anti-arpscan log enable
no anti-arpscan log enable
Enable or disable the log function of ARP
scanning prevention.
anti-arpscan trap enable
no anti-arpscan trap enable
Enable or disable the SNMP Trap function
of ARP scanning prevention.
show anti-arpscan [trust <ip | port |
supertrust-port> | prohibited <ip | port>]
Display the state of operation and
configuration of ARP scanning prevention.
Admin Mode
debug anti-arpscan <port | ip>
no debug anti-arpscan <port | ip>
Enable or disable the debug switch of ARP
scanning prevention.
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27.3 ARP Scanning Prevention Typical Examples
SWITCH B
E1/1
E1/19
SWITCH A E1/2
E1/2
PC Server
192.168.1.100/24
PC
Figure 27-1: ARP scanning prevention typical configuration example
In the network topology above, port E1/1 of SWITCH B is connected to port E1/19 of SWITCH
A, the port E1/2 of SWITCH A is connected to file server (IP address is 192.168.1.100/24), and
all the other ports of SWITCH A are connected to common PC. The following configuration can
prevent ARP scanning effectively without affecting the normal operation of the system.
SWITCH A configuration task sequence:
SwitchA(config)#anti-arpscan enable
SwitchA(config)#anti-arpscan recovery time 3600
SwitchA(config)#anti-arpscan trust ip 192.168.1.100 255.255.255.0
SwitchA(config)#interface ethernet1/2
SwitchA (Config-If-Ethernet1/2)#anti-arpscan trusted port
SwitchA (Config-If-Ethernet1/2)#exit
SwitchA(config)#interface ethernet1/19
SwitchA (Config-If-Ethernet1/19)#anti-arpscan supertrusted port
Switch A(Config-If-Ethernet1/19)#exit
SWITCHB configuration task sequence:
Switch B(config)# anti-arpscan enable
SwitchB(config)#interface ethernet1/1
SwitchB(Config-If-Ethernet1/1)#anti-arpscan trusted port
SwitchB(Config-If-Ethernet1/1)exit
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27.4 ARP Scanning Prevention Troubleshooting Help
ARP scanning prevention is disabled by default. After enabling ARP scanning
prevention, users can enable the debug switch, “debug anti-arpscan”, to view
debug information.
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Chapter 28 Prevent ARP Spoofing
Configuration
28.1 Overview
28.1.1 ARP (Address Resolution Protocol)
Generally speaking, ARP (RFC-826) protocol is mainly responsible of mapping IP address to
relevant 48-bit physical address, that is MAC address, for instance, IP address is 192.168.0.1,
network card Mac address is 00-30-4F-FD-1D-2B. What the whole mapping process is that a
host computer send broadcast data packet involving IP address information of destination host
computer, ARP request, and then the destination host computer send a data packet involving
its IP address and Mac address to the host, so two host computers can exchange data by
MAC address.
28.1.2 ARP Spoofing
In terms of ARP Protocol design, to reduce redundant ARP data communication on networks,
even though a host computer receives an ARP reply which is not requested by itself, it will also
insert an entry to its ARP cache table, so it creates a possibility of “ARP spoofing”. If the hacker
wants to snoop the communication between two host computers in the same network (even if
are connected by the switches), it sends an ARP reply packet to two hosts separately, and
make them misunderstand MAC address of the other side as the hacker host MAC address. In
this way, the direct communication is actually communicated indirectly among the hacker host
computer. The hackers not only obtain communication information they need, but also only
need to modify some information in data packet and forward successfully. In this sniff way, the
hacker host computer doesn’t need to configure intermix mode of network card, that is
because the data packet between two communication sides are sent to hacker host computer
on physical layer, which works as a relay.
28.1.3 How to prevent void ARP Spoofing
There are many sniff, monitor and attack behaviors based on ARP protocol in networks, and
most of attack behaviors are based on ARP spoofing, so it is very important to prevent ARP
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spoofing. ARP spoofing accesses normal network environment by counterfeiting legal IP
address firstly, and sends a great deal of counterfeited ARP application packets to switches,
after switches learn these packets, they will cover previously corrected IP, mapping of MAC
address, and then some corrected IP, MAC address mapping are modified to correspondence
relationship configured by attack packets so that the switch makes mistake on transfer packets,
and takes an effect on the whole network. Or the switches are made used of by vicious
attackers, and they intercept and capture packets transferred by switches or attack other
switches, host computers or network equipment.
What the essential method on preventing attack and spoofing switches based on ARP in
networks is to disable switch automatic update function; the cheater can’t modify corrected
MAC address in order to avoid wrong packets transfer and can’t obtain other information. At
one time, it doesn’t interrupt the automatic learning function of ARP. Thus it prevents ARP
spoofing and attack to a great extent.
28.2 Prevent ARP Spoofing configuration
The steps of preventing ARP spoofing configuration as below:
1. Disable ARP automatic update function
2. Disable ARP automatic learning function
3. Changing dynamic ARP to static ARP
1. Disable ARP automatic update function
Command Explanation
Global Mode
ip arp-security updateprotect
no ip arp-security updateprotect
Disable and enable ARP automatic update
function.
2. Disable ARP automatic learning function
Command Explanation
Global and VLAN Interface Mode
ip arp-security learnprotect
no ip arp-security learnprotect
Disable and enable ARP automatic learning
function.
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3. Function on changing dynamic ARP to static ARP
Command Explanation
Global and VLAN Interface Mode
ip arp-security convert Change dynamic ARP to static ARP.
28.3 Prevent ARP Spoofing Example
Switch
A B
C
Equipment Explanation
Equipment Configuration Quality
switch IP:192.168.2.4; mac: 00-00-00-00-00-04 1
A IP:192.168.2.1; mac: 00-00-00-00-00-01 1
B IP:192.168.1.2; mac: 00-00-00-00-00-02 1
C IP:192.168.2.3; mac: 00-00-00-00-00-03 some
There is a normal communication between B and C on above diagram. A wants switch to
forward packets sent by B to itself, so need switch sends the packets transfer from B to A.
firstly A sends ARP reply packet to switch, format is: 192.168.2.3, 00-00-00-00-00-01, mapping
its MAC address to C’s IP, so the switch changes IP address when it updates ARP list., then
data packet of 192.168.2.3 is transferred to 00-00-00-00-00-01 address (A MAC address).
In further, a transfers its received packets to C by modifying source address and destination
address, the mutual communicated data between B and C are received by A unconsciously.
Because the ARP list is update timely, another task for A is to continuously send ARP reply
packet, and refreshes switch ARP list.
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So it is very important to protect ARP list, configure to forbid ARP learning command in stable
environment, and then change all dynamic ARP to static ARP, the learned ARP will not be
refreshed, and protect for users.
Switch#config
Switch(config)#interface vlan 1
Switch(config-if-vlan1)#arp 192.168.2.1 00-00-00-00-00-01 interface ethernet 1/1
Switch(config-if-vlan1)#arp 192.168.2.2 00-00-00-00-00-02 interface ethernet 1/2
Switch(config-if-vlan1)#arp 192.168.2.3 00-00-00-00-00-03 interface ethernet 1/3
Switch(Config-If-Vlan3)#exit
Switch(Config)#ip arp-security learnprotect
Switch(Config)#
Switch(config)#ip arp-security convert
If the environment changing, it enable to forbid ARP refresh, once it learns ARP property, it
wont be refreshed by new ARP reply packet, and protect use data from sniffing.
Switch#config
Switch(config)#ip arp-security updateprotect
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Chapter 29 ARP GUARD Configuration
29.1 Introduction to ARP GUARD
There is serious security vulnerability in the design of ARP protocol, which is any network
device, can send ARP messages to advertise the mapping relationship between IP address
and MAC address. This provides a chance for ARP cheating. Attackers can send ARP
REQUEST messages or ARP REPLY messages to advertise a wrong mapping relationship
between IP address and MAC address, causing problems in network communication. The
danger of ARP cheating has two forms: 1. PC4 sends an ARP message to advertise that the IP
address of PC2 is mapped to the MAC address of PC4, which will cause all the IP messages
to PC2 will be sent to PC4, thus PC4 will be able to monitor and capture the messages to PC2;
2. PC4 sends ARP messages to advertise that the IP address of PC2 is mapped to an illegal
MAC address, which will prevent PC2 from receiving the messages to it. Particularly, if the
attacker pretends to be the gateway and do ARP cheating, the whole network will be
collapsed.
Figure 29-1: ARP GUARD schematic diagram
We utilize the filtering entries of the switch to protect the ARP entries of important network
devices from being imitated by other devices. The basic theory of doing this is that utilizing the
filtering entries of the switch to check all the ARP messages entering through the port, if the
source address of the ARP message is protected, the messages will be directly dropped and
will not be forwarded.
ARP GUARD function is usually used to protect the gateway from being attacked. If all the
accessed PCs in the network should be protected from ARP cheating, then a large number of
ARP GUARD address should be configured on the port, which will take up a big part of FFP
PC1 Switch
HUB A B C D
PC2
PC3
PC4 PC5 PC6
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entries in the chip, and as a result, might affect other applications. So this will be improper. It is
recommended that adopting FREE RESOURCE related accessing scheme. Please refer to
relative documents for details.
29.2 ARP GUARD Configuration Task List
1. Configure the protected IP address
Command Explanation
Port Mode
arp-guard ip <addr>
no arp-guard ip <addr> Configure/delete ARP GUARD address
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Chapter 30 Gratuitous ARP
Configuration
30.1 Introduction to Gratuitous ARP
Gratuitous ARP is a kind of ARP request that is sent by the host with its IP address as the
destination of the ARP request.
The basic working mode for the switch is as below: The Layer 3 interfaces of the switch can be
configured to advertise gratuitous ARP packets period or the switch can be configured to
enable to send gratuitous ARP packets in all the interfaces globally.
The purpose of gratuitous ARP is as below:
1. To reduce the frequency that the host sends ARP request to the switch. The hosts in the
network will periodically send ARP requests to the gateway to update the MAC address of
the gateway. If the switch advertises gratuitous ARP requests, the host will not have to
send these requests. This will reduce the frequency the hosts’ sending ARP requests for
the gateway’s MAC address.
2. Gratuitous ARP is a method to prevent ARP cheating. The switch’s advertising gratuitous
ARP request will force the hosts to update its ARP table cache. Thus, forged ARP of
gateway cannot function.
30.2 Gratuitous ARP Configuration Task List
1. Enable gratuitous ARP and configure the interval to send gratuitous ARP request
2. Display configurations about gratuitous ARP
1. Enable gratuitous ARP and configure the interval to send gratuitous ARP request.
Command Explanation
Global and VLAN Interface Mode.
ip gratuitous-arp <5-1200>
no ip gratuitous-arp
To enable gratuitous ARP and configure the
interval to send gratuitous ARP request.
The no command cancels the gratuitous ARP.
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2. Display configurations about gratuitous ARP
Command Explanation
Admin, Global and VLAN Interface Mode
show ip gratuitous-arp [interface VLAN
<1-4094>]
To display configurations about gratuitous
ARP.
30.3 Gratuitous ARP Configuration Example
Switch
Interface vlan10
192.168.15.254
255.255.255.0
PC1 PC2 PC3 PC4 PC5
Figure 30-1: Gratuitous ARP Configuration Example
For the network topology shown in the figure above, interface VLAN10 whose IP address is
192.168.15.254 and network address mask is 255.255.255.0 in the switch system. Five PCs –
PC1, PC2, PC3, PC4, PC5 are connected to the interface. Gratuitous ARP can be enabled
through the following configuration:
1. Configure global gratuitous ARP
Switch(config)#ip gratuitous-arp 300
Switch(config)#exit
2. Configure interface gratuitous ARP
Switch(config)#interface vlan 10
Switch(Config-if-Vlan10)#ip gratuitous-arp 300
Switch(Config-if-Vlan10)#exit
Switch(config) #exit
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30.4 Gratuitous ARP Troubleshooting
Gratuitous ARP is disabled by default. And when gratuitous ARP is enabled, the debugging
information about ARP packets can be retrieved through the command debug ARP send.
If gratuitous ARP is enabled in global configuration mode, it can be disabled only in global
configuration mode. If gratuitous ARP is configured in interface configuration mode, the
configuration can only be disabled in interface configuration mode. If gratuitous ARP is
enabled in both global and interface configuration mode, and the sending interval of gratuitous
ARP is configured in both configuration modes, the switch takes the value which is configured
in interface configuration mode.
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Chapter 31 DHCP Configuration
31.1 Introduction to DHCP
DHCP [RFC2131] is the acronym for Dynamic Host Configuration Protocol. It is a protocol that
assigns IP address dynamically from the address pool as well as other network configuration
parameters such as default gateway, DNS server, and default route and host image file
position within the network. DHCP is the enhanced version of BOOTP. It is a mainstream
technology that can not only provide boot information for diskless workstations, but can also
release the administrators from manual recording of IP allocation and reduce user effort and
cost on configuration. Another benefit of DHCP is it can partially ease the pressure on IP
demands, when the user of an IP leaves the network that IP can be assigned to another user.
DHCP is a client-server protocol, the DHCP client requests the network address and
configuration parameters from the DHCP server; the server provides the network address and
configuration parameters for the clients; if DHCP server and clients are located in different
subnets, DHCP relay is required for DHCP packets to be transferred between the DHCP client
and DHCP server. The implementation of DHCP is shown below:
Figure 31-1: DHCP protocol interaction
Explanation:
Discover
Offer
Request
Ack
DHCP SERVER DHCP CLIENT
1． DHCP client broadcasts DHCPDISCOVER packets in the local subnet.
2． On receiving the DHCPDISCOVER packet, DHCP server sends a DHCPOFFER packet
along with IP address and other network parameters to the DHCP client.
3． DHCP client broadcast DHCPREQUEST packet with the information for the DHCP server
it selected after selecting from the DHCPOFFER packets.
4． The DHCP server selected by the client sends a DHCPACK packet and the client gets an
IP address and other network configuration parameters.
The above four steps finish a Dynamic host configuration assignment process. However, if the
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DHCP server and the DHCP client are not in the same network, the server will not receive the
DHCP broadcast packets sent by the client, therefore no DHCP packets will be sent to the
client by the server. In this case, a DHCP relay is required to forward such DHCP packets so
that the DHCP packets exchange can be completed between the DHCP client and server.
Switch can act as both a DHCP server and a DHCP relay. DHCP server supports not only
dynamic IP address assignment, but also manual IP address binding (i.e. specify a specific IP
address to a specified MAC address or specified device ID over a long period. The differences
and relations between dynamic IP address allocation and manual IP address binding are: 1) IP
address obtained dynamically can be different every time; manually bound IP address will be
the same all the time. 2) The lease period of IP address obtained dynamically is the same as
the lease period of the address pool, and is limited; the lease of manually bound IP address is
theoretically endless. 3) Dynamically allocated address cannot be bound manually. 4)
Dynamic DHCP address pool can inherit the network configuration parameters of the dynamic
DHCP address pool of the related segment.
31.2 DHCP Server Configuration
DHCP Sever Configuration Task List:
1. Enable/Disable DHCP service
2. Configure DHCP Address pool
(1) Create/Delete DHCP Address pool
(2) Configure DHCP address pool parameters
(3) Configure manual DHCP address pool parameters
3. Enable logging for address conflicts
1. Enable/Disable DHCP service
Command Explanation
Global Mode
service dhcp
no service dhcp
Enable DHCP server. The no command
disables DHCP server.
Port Mode
ip dhcp disbale
no ip dhcp disable
The port disables DHCP services, the no
command enables DHCP services.
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2. Configure DHCP Address pool
(1) Create/Delete DHCP Address pool
Command Explanation
Global Mode
ip dhcp pool <name>
no ip dhcp pool <name>
Configure DHCP Address pool. The no
operation cancels the DHCP Address pool.
(2) Configure DHCP address pool parameters
Command Explanation
DHCP Address Pool Mode
network-address <network-number>
[mask | prefix-length]
no network-address
Configure the address scope that can be
allocated to the address pool. The no
operation of this command cancels the
allocation address pool.
default-router
[<address1>[<address2>[…<address8>
]]]
no default-router
Configure default gateway for DHCP clients.
The no operation cancels the default
gateway.
dns-server
[<address1>[<address2>[…<address8>
]]]
no dns-server
Configure DNS server for DHCP clients. The
no command deletes DNS server
configuration.
domain-name <domain>
no domain-name
Configure Domain name for DHCP clients;
the “no domain-name” command deletes
the domain name.
netbios-name-server
[<address1>[<address2>[…<address8>
]]]
no netbios-name-server
Configure the address for WINS server. The
no operation cancels the address for server.
netbios-node-type
{b-node|h-node|m-node|p-node|<type-n
umber>}
no netbios-node-type
Configure node type for DHCP clients. The
no operation cancels the node type for
DHCP clients.
bootfile <filename>
no bootfile
Configure the file to be imported for DHCP
clients on boot up. The no command
cancels this operation.
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next-server
[<address1>[<address2>[…<address8>
]]]
no next-server
[<address1>[<address2>[…<address8>
]]]
Configure the address of the server hosting
file for importing. The no command deletes
the address of the server hosting file for
importing.
option <code> {ascii <string> | hex
<hex> | ipaddress <ipaddress>}
no option <code>
Configure the network parameter specified
by the option code. The no command
deletes the network parameter specified by
the option code.
lease { days [hours][minutes] | infinite }
no lease
Configure the lease period allocated to
addresses in the address pool. The no
command deletes the lease period allocated
to addresses in the address pool.
max-lease-time {[<days>] [<hours>]
[<minutes>] | infinite}
no max-lease-time
Set the maximum lease time for the
addresses in the address pool; the no
command restores the default setting.
Global Mode
ip dhcp excluded-address
<low-address> [<high-address>]
no ip dhcp excluded-address
<low-address> [<high-address>]
Exclude the addresses in the address pool
that are not for dynamic allocation.
(3) Configure manual DHCP address pool parameters
Command Explanation
DHCP Address Pool Mode
hardware-address <hardware-address>
[{Ethernet | IEEE802|<type-number>}]
no hardware-address
Specify/delete the hardware address
when assigning address manually.
host <address> [<mask> |
<prefix-length> ]
no host
Specify/delete the IP address to be
assigned to the specified client when
binding address manually.
client-identifier <unique-identifier>
no client-identifier
Specify/delete the unique ID of the user
when binding address manually.
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3. Enable logging for address conflicts
Command Explanation
Global Mode
ip dhcp conflict logging
no ip dhcp conflict logging
Enable/disable logging for DHCP address to
detect address conflicts.
Admin Mode
clear ip dhcp conflict <address | all > Delete a single address conflict record or all
conflict records.
31.3 DHCP Relay Configuration
When the DHCP client and server are in different segments, DHCP relay is required to transfer
DHCP packets. Adding a DHCP relay makes it unnecessary to configure a DHCP server for
each segment, one DHCP server can provide the network configuration parameter for clients
from multiple segments, which is not only cost-effective but also management-effective.
DHCP Ser verDHCP Cl i ent
DHCPDi scover (Br oadcast )
DHCPOFFER(Uni cast )
DHCPREQUEST(Br oadcast )
DHCPACK(Uni cast )
DHCPDi scover
DHCP Rel ay
DHCPOFFER
DHCPREQUEST
DHCPACK
Figure 31-2: DHCP relay
As shown in the above figure, the DHCP client and the DHCP server are in different networks,
the DHCP client performs the four DHCP steps as usual yet DHCP relay is added to the
process.
1. The client broadcasts a DHCPDISCOVER packet, and DHCP relay inserts its own IP
address to the relay agent field in the DHCPDISCOVER packet on receiving the
packet, and forwards the packet to the specified DHCP server (for DHCP frame format,
please refer to RFC2131).
2. On the receiving the DHCPDISCOVER packets forwarded by DHCP relay, the DHCP
server sends the DHCPOFFER packet via DHCP relay to the DHCP client.
3. DHCP client chooses a DHCP server and broadcasts a DHCPREQUEST packet,
DHCP relay forwards the packet to the DHCP server after processing.
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4. On receiving DHCPREQUEST, the DHCP server responds with a DHCPACK packet
via DHCP relay to the DHCP client.
DHCP Relay Configuration Task List:
1. Enable DHCP relay.
2. Configure DHCP relay to forward DHCP broadcast packet.
3. Configure share-vlan
1. Enable DHCP relay.
Command Explanation
Global Mode
service dhcp
no service dhcp
DHCP server and DHCP relay is enabled as the
DHCP service is enabled.
2. Configure DHCP relay to forward DHCP broadcast packet.
Command Explanation
Global Mode
ip forward-protocol udp bootps
no ip forward-protocol udp bootps
The UDP port 67 is used for DHCP broadcast
packet forwarding.
VLAN Interface Mode
ip helper-address <ipaddress>
no ip helper-address <ipaddress>
Set the destination IP address for DHCP relay
forwarding; the “no ip helper-address
<ipaddress>“command cancels the setting.
3. Configure share-VLAN
When the user want to use layer 2 device as DHCP relay, there is the number limitation that
create layer 3 interface on layer 2 device, but using the layer 3 interface of share-VLAN (it may
include many sub-VLAN, however a sub-VLAN only correspond to a share-VLAN) can
implement DHCP relay forwarding, and the relay device needs to enable option82 function at
the same time.
Command Explanation
Global Mode
ip dhcp relay share-vlan <vlanid>
sub-vlan <vlanlist>
no dhcp relay share-vlan
Create or delete share-VLAN and it's sub-VLAN.
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31.4 DHCP Configuration Examples
Scenario 1:
Too save configuration efforts of network administrators and users, a company is using switch
as a DHCP server. The Admin VLAN IP address is 10.16.1.2/16. The local area network for the
company is divided into network A and B according to the office locations. The network
configurations for location A and B are shown below.
PoolA(network 10.16.1.0) PoolB(network 10.16.2.0)
Device IP address Device IP address
Default gateway 10.16.1.200
10.16.1.201
Default gateway 10.16.1.200
10.16.1.201
DNS server 10.16.1.202 DNS server 10.16.1.202
WINS server 10.16.1.209 WWW server 10.16.1.209
WINS node type H-node
Lease 3 days Lease 1day
In location A, a machine with MAC address 00-03-22-23-dc-ab is assigned with a fixed IP
address of 10.16.1.210 and named as “management”.
Switch(config)#service dhcp
Switch(config)#interface vlan 1
Switch(Config-Vlan-1)#ip address 10.16.1.2 255.255.0.0
Switch(Config-Vlan-1)#exit
Switch(config)#ip dhcp pool A
Switch(dhcp-A-config)#network 10.16.1.0 24
Switch(dhcp-A-config)#lease 3
Switch(dhcp-A-config)#default-route 10.16.1.200 10.16.1.201
Switch(dhcp-A-config)#dns-server 10.16.1.202
Switch(dhcp-A-config)#netbios-name-server 10.16.1.209
Switch(dhcp-A-config)#netbios-node-type H-node
Switch(dhcp-A-config)#exit
Switch(config)#ip dhcp excluded-address 10.16.1.200 10.16.1.201
Switch(config)#ip dhcp pool B
Switch(dhcp-B-config)#network 10.16.2.0 24
Switch(dhcp-B-config)#lease 1
Switch(dhcp-B-config)#default-route 10.16.2.200 10.16.2.201
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Switch(dhcp-B-config)#dns-server 10.16.2.202
Switch(dhcp-B-config)#option 72 ip 10.16.2.209
Switch(dhcp-config)#exit
Switch(config)#ip dhcp excluded-address 10.16.2.200 10.16.2.201
Switch(config)#ip dhcp pool A1
Switch(dhcp-A1-config)#host 10.16.1.210
Switch(dhcp-A1-config)#hardware-address 00-03-22-23-dc-ab
Switch(dhcp-A1-config)#exit
Usage Guide: When a DHCP/BOOTP client is connected to a VLAN1 port of the switch, the
client can only get its address from 10.16.1.0/24 instead of 10.16.2.0/24. This is because the
broadcast packet from the client will be requesting the IP address in the same segment of the
VLAN interface after VLAN interface forwarding, and the VLAN interface IP address is
10.16.1.2/24, therefore the IP address assigned to the client will belong to 10.16.1.0/24.
If the DHCP/BOOTP client wants to have an address in 10.16.2.0/24, the gateway forwarding
broadcast packets of the client must belong to 10.16.2.0/24. The connectivity between the
client gateway and the switch must be ensured for the client to get an IP address from the
10.16.2.0/24 address pool.
Scenario 2:
E1/1
192.168.1.1
E1/2
10.1.1.1 DHCP Client
DHCP Relay DHCP Client DHCP Server
10.1.1.10
DHCP Client
Figure 31-3: DHCP Relay Configuration
As shown in the above figure, route switch is configured as a DHCP relay. The DHCP server
address is 10.1.1.10, the configuration steps is as follows:
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Switch(config)#service dhcp
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 192.168.1.1 255.255.255.0
Switch(Config-if-Vlan1)#exit
Switch(config)#vlan 2
Switch(Config-Vlan-2)#exit
Switch(config)#interface Ethernet 1/2
Switch(Config-Erthernet1/2)#switchport access vlan 2
Switch(Config-Erthernet1/2)#exit
Switch(config)#interface vlan 2
Switch(Config-if-Vlan2)#ip address 10.1.1.1 255.255.255.0
Switch(Config-if-Vlan2)#exit
Switch(config)#ip forward-protocol udp bootps
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip help-address 10.1.1.10
Switch(Config-if-Vlan1)#exit
Note: It is recommended to use the combination of command ip forward-protocol udp
<port> and ip helper-address <ipaddress>. ip help-address can only be configured for
ports on layer 3 and cannot be configured on layer 2 ports directly.
Scenario 3:
Figure 31-4: DHCP configuration example
As shown in the above figure, PC1 is DHCP client, obtain the address through DHCP. Switch1
is a layer 2 access device, it enables DHCP Relay and option82 functions, Ethernet1/2 is a
access port, belongs to VLAN3, Ethernet1/3 is a trunk port, connects to DHCP Server, DHCP
Server address is 192.168.40.199. Switch1 creates VLAN1 and interface VLAN1, configure IP
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address of interface VLAN1 as 192.168.40.50, configure the address of DHCP Relay
forwarding as 192.168.40.199, configure VLAN3 as a sub-VLAN of VLAN1. The configuration
is as follows:
switch(config)#vlan 1
switch(config)#vlan 3
switch(config)#interface ethernet 1/2
Switch(Config-If-Ethernet1/2)#switchport access vlan 3
switch(config)#interface ethernet 1/3
Switch(Config-If-Ethernet1/2)#switchport mode trunk
switch(config)#service dhcp
switch(config)#ip forward-protocol udp bootps
switch(config)#ip dhcp relay information option
switch(config)#ip dhcp relay share-vlan 1 sub-vlan 3
switch(config-if-vlan1)#ip address 192.168.40.50 255.255.255.0
switch(config-if-vlan1)#ip helper-address 192.168.40.199
31.5 DHCP Troubleshooting
If the DHCP clients cannot obtain IP addresses and other network parameters, the following
procedures can be followed when DHCP client hardware and cables have been verified ok.
Verify the DHCP server is running, start the related DHCP server if not running.
In such case, DHCP server should be examined for an address pool that is in the
same segment of the switch VLAN, such a pool should be added if not present, and
(This does not indicate switch cannot assign IP address for different segments, see
solution 2 for details.)
In DHCP service, pools for dynamic IP allocation and manual binding are conflicting,
i.e., if command “network-address” and “host” are run for a pool, only one of them
will take effect; furthermore, in manual binding, only one IP-MAC binding can be
configured in one pool. If multiple bindings are required, multiple manual pools can
be created and IP-MAC bindings set for each pool. New configuration in the same
pool overwrites the previous configuration.
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Chapter 32 DHCPv6 Configuration
32.1 Introduction to DHCPv6
DHCPv6 [RFC3315] is the IPv6 version for Dynamic Host Configuration Protocol (DHCP). It is
a protocol that assigns IPv6 address as well as other network configuration parameters such
as DNS address, and domain name to DHCPv6 client, DHCPv6 is a conditional auto address
configuration protocol relative to IPv6. In the conditional address configuration process,
DHCPv6 server assigns a complete IPv6 address to client, and provides DNS address,
domain name and other configuration information, maybe the DHCPv6 packet can transmit
through relay delegation, at last the binding of IPv6 address and client can be recorded by
DHCPv6 server, all that can enhance the management of network; DHCPv6 server can also
provide non state DHCPv6 service, that is only assigns DNS address and domain name and
other configuration information but not assigns IPv6 address, it can solve the bug of IPv6 auto
address configuration in non state; DHCPv6 can provide extend function of DHCPv6 prefix
delegation, upstream route can assign address prefix to downstream route automatically, that
achieve the IPv6 address auto assignment in levels of network environment, and resolved the
problem of ISP and IPv6 network dispose.
There are three entities in the DHCPv6 protocol – the client, the relay and the server. The
DHCPv6 protocol is based on the UDP protocol. The DHCPv6 client sends request messages
to the DHCP server or DHCP relay with the destination port as 547, and the DHCPv6 server
and relay send replying messages with the destination port as 546. The DHCPv6 client sends
solicit or request messages with the multicast address – ff02::1:2 for DHCP relay and server.
Figure 32-1: DHCPv6 negotiation
When a DHCPv6 client tries to request an IPv6 address and other configurations from the
DHCPv6 server, the client has to find the location of the DHCP server, and then request
configurations from the DHCP server.
Reply (Unicast)
Request (Multicast)
Advertise (Unicast)
Solicit (Multicast)
DHCPv6 SERVER DHCPv6 CLIENT
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1. In the time of located server, the DHCP client tries to find a DHCPv6 server by
broadcasting a SOLICIT packet to all the DHCP delay delegation and server with
broadcast address as FF02::1:2.
2. Any DHCP server which receives the request, will reply the client with an
ADVERTISE message, which includes the identity of the server –DUID, and its
priority.
3. It is possible that the client receives multiple ADVERTISE messages. The client
should select one and reply it with a REQUEST message to request the address
which is advertised in the ADVERTISE message.
4. The selected DHCPv6 server then confirms the client about the IPv6 address and
any other configuration with the REPLY message.
The above four steps finish a Dynamic host configuration assignment process. However, if the
DHCPv6 server and the DHCPv6 client are not in the same network, the server will not receive
the DHCPv6 broadcast packets sent by the client, therefore no DHCPv6 packets will be sent to
the client by the server. In this case, a DHCPv6 relay is required to forward such DHCPv6
packets so that the DHCPv6 packets exchange can be completed between the DHCPv6 client
and server.
At the time this manual is written, DHCPv6 server, relay and prefix delegation client have been
implemented on the switch. When the DHCPv6 relay receives any messages from the
DHCPv6 client, it will encapsulate the request in a Relay-forward packet and deliver it to the
next DHCPv6 relay or the DHCPv6 server. The DHCPv6 messages coming from the server
will be encapsulated as relay reply packets to the DHCPv6 relay. The relay then removes the
encapsulation and delivers it the DHCPv6 client or the next DHCPv6 relay in the network.
For DHCPv6 prefix delegation where DHCPv6 server is configured on the PE router and
DHCPv6 client it configured on the CPE router, the CPE router is able to send address prefix
allocation request to the PE router and get a pre-configured address prefix, but not set the
address prefix manually. The protocol negotiation between the client and the prefix delegation
client is quite similar to that when getting a DHCPv6 address. Then the CPE router divides the
allocated prefix – whose length should be less than 64 characters, into 64 subnets. The
divided address prefix will be advertised through routing advertisement messages (RA) to the
host directly connected to the client.
32.2 DHCPv6 Server Configuration
DHCPv6 server configuration task list as below:
1. To enable/disable DHCPv6 service
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2. To configure DHCPv6 address pool
（1） To achieve/delete DHCPv6 address pool
（2） To configure parameter of DHCPv6 address pool
3. To enable DHCPv6 server function on port
1. To enable/disable DHCPv6 service
Command Explanation
Global Mode
service dhcpv6
no service dhcpv6 To enable DHCPv6 service.
2. To configure DHCPv6 address pool
（1）To achieve/delete DHCPv6 address pool
Command Explanation
Global Mode
ipv6 dhcp pool <poolname>
no ipv6 dhcp pool <poolname> To configure DHCPv6 address pool.
（2）To configure parameter of DHCPv6 address pool
Command Explanation
DHCPv6 Address Pool Mode
network-address
<ipv6-pool-start-address>
{<ipv6-pool-end-address> |
<prefix-length>} [eui-64]
no network-address
To configure the range of IPv6 address
assignable of address pool.
dns-server <ipv6-address>
no dns-server <ipv6-address>
To configure DNS server address for
DHCPv6 client.
domain-name <domain-name>
no domain-name <domain-name> To configure DHCPv6 client domain name.
excluded-address <ipv6-address>
no excluded-address <ipv6-address>
To exclude IPv6 address which isn’t used for
dynamic assignment in address pool.
lifetime {<valid-time> | infinity}
{<preferred-time> | infinity}
no lifetime
To configure valid time or preferred time of
DHCPv6 address pool.
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3. To enable DHCPv6 server function on port.
Command Explanation
VLAN Interface Mode
ipv6 dhcp server <poolname>
[preference <value>] [rapid-commit]
[allow-hint]
no ipv6 dhcp server <poolname>
To enable DHCPv6 server function on
specified port, and binding the used
DHCPv6 address pool.
32.3 DHCPv6 Relay Delegation Configuration
DHCPv6 relay delegation configuration task list as below:
1． To enable/disable DHCPv6 service
2． To configure DHCPv6 relay delegation on port
1. To enable DHCPv6 service
Command Explanation
Global Mode
service dhcpv6
no service dhcpv6 To enableDHCPv6 service.
2. To configure DHCPv6 relay delegation on port
Command Explanation
VLAN Interface Mode
ipv6 dhcp relay destination
{[<ipv6-address>] [interface
{ <interface-name> | vlan <1-4096>}]}
no ipv6 dhcp relay destination
{[<ipv6-address>] [interface
{ <interface-name> | vlan <1-4096>}]}
To specify the destination address of
DHCPv6 relay transmit; The no form of
this command delete the configuration.
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32.4 DHCPv6 Prefix Delegation Server Configuration
DHCPv6 prefix delegation server configuration task list as below:
1. To enable/delete DHCPv6 service
2. To configure prefix delegation pool
3. To configure DHCPv6 address pool
（1） To achieve/delete DHCPv6 address pool
（2） To configure prefix delegation pool used by DHCPv6 address pool
（3） To configure static prefix delegation binding
（4） To configure other parameters of DHCPv6 address pool
4. To enable DHCPv6 prefix delegation server function on port
1. To enable/delete DHCPv6 service
Command Explanation
Global Mode
service dhcpv6
no service dhcpv6 To enable DHCPv6 service.
2. To configure prefix delegation pool
Command Explanation
Global Mode
ipv6 local pool <poolname>
<prefix|prefix-length>
<assigned-length>
no ipv6 local pool <poolname>
To configure prefix delegation pool.
3. To configure DHCPv6 address pool
（1）To achieve/delete DHCPv6 address pool
Command Explanation
Global Mode
ipv6 dhcp pool <poolname>
no ipv6 dhcp pool <poolname> To configure DHCPv6 address pool.
（2）To configure prefix delegation pool used by DHCPv6 address pool
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Command Explanation
DHCPv6 Address Pool Mode
prefix-delegation pool <poolname>
[lifetime <valid-time> <preferred-time>]
no prefix-delegation pool <poolname>
To specify prefix delegation pool used by
DHCPv6 address pool, and assign usable
prefix to client.
（3） To configure static prefix delegation binding
Command Explanation
DHCPv6 Address Pool Mode
prefix-delegation
<ipv6-prefix/prefix-length>
<client-DUID> [iaid <iaid>] [lifetime
<valid-time> <preferred-time>]
no prefix-delegation
<ipv6-prefix/prefix-length>
<client-DUID> [iaid <iaid>]
To specify IPv6 prefix and any prefix
required static binding by client.
（4） To configure other parameter of DHCPv6 address pool
Command Explanation
DHCPv6 Address Pool Mode
dns-server <ipv6-address>
no dns-server <ipv6-address>
To configure DNS server address for
DHCPv6 client.
domain-name <domain-name>
no domain-name <domain-name>
To configure domain name for DHCPv6
client.
4. To enable DHCPv6 prefix delegation server function on port
Command Explanation
VLAN Interface Mode
ipv6 dhcp server <poolname>
[preference <value>] [rapid-commit]
[allow-hint]
no ipv6 dhcp server <poolname>
To enable DHCPv6 server function on
specified port, and binding used DHCPv6
address pool.
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32.5 DHCPv6 Prefix Delegation Client Configuration
DHCPv6 prefix delegation client configuration task list as below:
1. To enable/disable DHCPv6 service
2. To enable DHCPv6 prefix delegation client function on port
1. To enable/disable DHCPv6 service
Command Explanation
Global Mode
service dhcpv6
no service dhcpv6 To enable DHCPv6 service.
2. To enable DHCPv6 prefix delegation client function on port
Command Explanation
VLAN Interface Mode
ipv6 dhcp client pd <prefix-name>
[rapid-commit]
no ipv6 dhcp client pd
To enable client prefix delegation request
function on specified port, and the prefix
obtained associate with universal prefix
configured.
32.6 DHCPv6 Configuration Examples
Example1:
When deploying IPv6 networking, the switch can be configured as DHCPv6 server in order to
manage the allocation of IPv6 addresses. Both the state and the stateless DHCPv6 are
supported.
Topology:
The access layer use Switch1 switch to connect users of dormitory buildings and it is
configured as DHCPv6 relay delegation; Switch3 is configured as DHCPv6 server in
secondary aggregation layer, and connected with backbone network or higher aggregation
layers; The Windows Vista which be provided with DHCPv6 client must load on PC.
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Usage guide:
Switch3 configuration：
Switch3>enable
Switch3#config
Switch3(config)#service dhcpv6
Switch3(config)#ipv6 dhcp pool EastDormPool
Switch3(dhcpv6-EastDormPool-config)#network-address 2001:da8:100:1::1
2001:da8:100:1::100
Switch3(dhcpv6-EastDormPool-config)#excluded-address 2001:da8:100:1::1
Switch3(dhcpv6-EastDormPool-config)#dns-server 2001:da8::20
Switch3(dhcpv6-EastDormPool-config)#dns-server 2001:da8::21
Switch3(dhcpv6-EastDormPool-config)#domain-name dhcpv6.com
Switch3(dhcpv6-EastDormPool-config)#lifetime 1000 600
Switch3(dhcpv6-EastDormPool-config)#exit
Switch3(config)#interface vlan 1
Switch3(Config-if-Vlan1)#ipv6 address 2001:da8:1:1::1/64
Switch3(Config-if-Vlan1)#exit
Switch3(config)#interface vlan 10
Switch3(Config-if-Vlan10)#ipv6 address 2001:da8:10:1::1/64
Switch3(Config-if-Vlan10)#ipv6 dhcp server EastDormPool preference 80
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Switch3(Config-if-Vlan10)#exit
Switch3(config)#
Switch2 configuration：
Switch2>enable
Switch2#config
Switch2(config)#service dhcpv6
Switch2(config)#interface vlan 1
Switch2(Config-if-Vlan1)#ipv6 address 2001:da8:1:1::2/64
Switch2(Config-if-Vlan1)#exit
Switch2(config)#interface vlan 10
Switch2(Config-if-Vlan10)#ipv6 address 2001:da8:10:1::2/64
Switch2(Config-if-Vlan10)#exit
Switch2(config)#interface vlan 100
Switch2(Config-if-Vlan100)#ipv6 address 2001:da8:100:1::1/64
Switch2(Config-if-Vlan100)#no ipv6 nd suppress-ra
Switch2(Config-if-Vlan100)#ipv6 nd managed-config-flag
Switch2(Config-if-Vlan100)#ipv6 nd other-config-flag
Switch2(Config-if-Vlan100)#exit
Switch2(config)#
Switch1 configuration:
Switch1(config)#service dhcpv6
Switch2(config)#interface vlan 1
Switch2(Config-if-Vlan1)#ipv6 address 2001:da8:100:1::2/64
Switch2(Config-if-Vlan1)#ipv6 dhcp relay destination 2001:da8:10:1::1
32.7 DHCPv6 Troubleshooting
If the DHCPv6 clients cannot obtain IPv6 addresses and other network parameters, the
following procedures can be followed when DHCPv6 client hardware and cables have been
verified ok:
Verify the DHCPv6 server is running, start the related DHCP v6 server function if not
running;
If the DHCPv6 clients and servers are not in the same physical network, verify the
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router responsible for DHCPv6 packet forwarding has DHCPv6 relay function. If
DHCPv6 relay is not available for the intermediate router, it is recommended to
replace the router or upgrade its software to one that has a DHCPv6 relay function;
Sometimes hosts are connected to the DHCPv6 enabled switches, but can not get
IPv6 addresses. In this situation, it should be checked first whether the ports which
the hosts are connected to, are connected with the port which the DHCPv6 server is
connected to. If connected directly, it should be checked then whether the IPv6
address pool of the VLAN which the port belongs to, is in the same subnet with the
address pool configure in the DHCPv6 server; If not connected directly, and any
layer three DHCPv6 relay is configured between the hosts and the DHCPv6 server, it
should be checked first whether an valid IPv6 address has been configured for the
switch interface which the hosts are connected to. If not configured, configure an
valid IPv6 address. If configured, it should be checked whether the configured IPv6
address is in the same subnet with the DHCPv6 server. If not, please add it to the
address pool.
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Chapter 33 DHCP Option 82
Configuration
33.1 Introduction to DHCP Option 82
DHCP option 82 is the Relay Agent Information Option, its option code is 82. DHCP option 82
is aimed at strengthening the security of DHCP servers and improving the IP address
configuration policy. The Relay Agent adds option 82 (including the client’s physical access
port, the access device ID and other information), to the DHCP request message from the
client then forwards the message to DHCP server. When the DHCP server which supports the
option 82 function receives the message, it will allocate an IP address and other configuration
information for the client according to preconfigured policies and the option 82 information in
the message. At the same time, DHCP server can identify all the possible DHCP attack
messages according to the information in option 82 and defend against them. DHCP Relay
Agent will peel the option 82 from the reply messages it receives, and forward the reply
message to the specified port of the network access device, according to the physical port
information in the option. The application of DHCP option 82 is transparent for the client.
33.1.1 DHCP Option 82 Message Structure
A DHCP message can have several option segments; option 82 is one of them. It has to be
placed after other options but before option 255. The following is its format:
Code: represents the sequence number of the relay agent information option, the option 82 is
called so because RFC3046 is defined as 82.
Len: the number of bytes in Agent Information Field, not including the two bytes in Code
segment and Len segment.
Option 82 can have several sub-options, and need at least one sub-option. RFC3046 defines
the following two sub-options, whose formats are showed as follows:
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SubOpt: the sequence number of sub-option, the sequence number of Circuit ID sub-option is
1, the sequence number of Remote ID sub-option is 2.
Len: the number of bytes in Sub-option Value, not including the two bytes in SubOpt segment
and Len segment.
33.1.2 Option 82 Working Mechanism
DHCP Relay Agent
DHCP option 82 flow chart
If the DHCP Relay Agent supports option 82, the DHCP client should go through the following
four steps to get its IP address from the DHCP server: discover, offer, select and acknowledge.
The DHCP protocol follows the procedure below:
1）DHCP client sends a request broadcast message while initializing. This request message
does not have option 82.
2）DHCP Relay Agent will add the option 82 to the end of the request message it receives, then
relay and forward the message to the DHCP server. By default, the sub-option 1 of option 82
(Circuit ID) is the interface information of the switch connected to the DHCP client (VLAN
name and physical port name), but the users can configure the Circuit ID as they wish. The
sub-option 2 of option 82(Remote ID) is the MAC address of the DHCP relay device.
3）After receiving the DHCP request message, the DHCP server will allocate IP address and
DHCP Request DHCP Request Option82
DHCP Reply
Option82DHCP Reply
DHCP Client DHCP Server
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other information for the client according to the information and preconfigured policy in the
option segment of the message. Then it will forward the reply message with DHCP
configuration information and option 82 information to DHCP Relay Agent.
4）DHCP Relay Agent will peel the option 82 information from the replay message sent by
DHCP server, and then forward the message with DHCP configuration information to the
DHCP client.
33.2 DHCP Option 82 Configuration Task List
1. Enabling the DHCP option 82 of the Relay Agent
2. Configure the DHCP option 82 attributes of the interface
3. Enable the DHCP option 82 of server
4. Configure DHCP option 82 default format of Relay Agent
5. Configure delimiter
6. Configure creation method of option82
7. Diagnose and maintain DHCP option 82
1. Enabling the DHCP option 82 of the Relay Agent.
Command Explanation
Global Mode
ip dhcp relay information option
no ip dhcp relay information option
Set this command to enable the option 82
function of the switch Relay Agent. The “no
ip dhcp relay information option” is used to
disable the option 82 function of the switch
Relay Agent.
2. Configure the DHCP option 82 attributes of the interface
Command Explanation
VLAN Interface Mode
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ip dhcp relay information policy {drop |
keep | replace}
no ip dhcp relay information policy
This command is used to set the
retransmitting policy of the system for the
received DHCP request message which
contains option 82. The drop mode means
that if the message has option82, then the
system will drop it without processing; keep
mode means that the system will keep the
original option 82 segment in the message,
and forward it to the server to process;
replace mode means that the system will
replace the option 82 segment in the
existing message with its own option 82,
and forward the message to the server to
process. The “no ip dhcp relay information
policy” will set the retransmitting policy of
the option 82 DCHP message as “replace”.
ip dhcp relay information option
subscriber-id {standard | <circuit-id>}
no ip dhcp relay information option
subscriber-id
This command is used to set the format of
option 82 sub-option1(Circuit ID option)
added to the DHCP request messages
from interface, standard means the
standard VLAN name and physical port
name format,
like”VLAN2+Ethernet1/12”,<circuit-id> is
the circuit-id contents of option 82 specified
by users, which is a string no longer than
64characters. The” no ip dhcp relay
information option subscriber-id”
command will set the format of added
option 82 sub-option1 (Circuit ID option) as
standard format.
Global Mode
ip dhcp relay information option
remote-id {standard | <remote-id>}
no ip dhcp relay information option
remote-id
Set the suboption2 (remote ID option)
content of option 82 added by DHCP
request packets (They are received by the
interface). The no command sets the
additive suboption2 (remote ID option)
format of option 82 as standard.
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3. Enable the DHCP option 82 of server.
Command Explanation
Global Mode
ip dhcp server relay information enable
no ip dhcp server relay information
enable
This command is used to enable the switch
DHCP server to identify option82. The “no
ip dhcp server relay information enable”
command will make the server ignore the
option 82.
4. Configure DHCP option 82 default format of Relay Agent
Command Explanation
Global Mode
ip dhcp relay information option
subscriber-id format {hex | acsii | vs-hp}
Set subscriber-id format of Relay Agent
option82.
ip dhcp relay information option
remote-id format {default | vs-hp}
Set remote-id format of Relay Agent
option82.
5. Configure delimiter
Command Explanation
Global Mode
ip dhcp relay information option
delimiter [colon | dot | slash | space]
no ip dhcp relay information option
delimiter
Set the delimiter of each parameter for
suboption of option82 in global mode, no
command restores the delimiter as slash.
6. Configure creation method of option82
Command Explanation
Global Mode
ip dhcp relay information option
self-defined remote-id {hostname | mac |
string WORD}
no ip dhcp relay information option
self-defined remote-id
Set creation method for option82, users
can define the parameters of remote-id
suboption by themselves
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ip dhcp relay information option
self-defined remote-id format [ascii |
hex]
Set self-defined format of remote-id for
relay option82.
ip dhcp relay information option
self-defined subscriber-id {vlan | port | id
(switch-id (mac | hostname)|
remote-mac)| string WORD }
no ip dhcp relay information option
self-defined subscriber-id
Set creation method for option82, users
can define the parameters of circuit-id
suboption by themselves
ip dhcp relay information option
self-defined subscriber-id format [ascii |
hex]
Set self-defined format of circuit-id for relay
option82.
7. Diagnose and maintain DHCP option 82
Command Explanation
Admin Mode
show ip dhcp relay information option
This command will display the state
information of the DHCP option 82 in the
system, including option82 enabling switch,
the interface retransmitting policy, the
circuit ID mode and the DHCP server
option82 enabling switch.
debug ip dhcp relay packet
This command is used to display the
information of data packets processing in
DHCP Relay Agent, including the “add” and
“peel” action of option 82.
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33.3 DHCP Option 82 Application Examples
Vlan2:ethernet1/3 DHCP Relay Agent
Switch3 Switch1
DHCP Client PC1
Vlan3
Vlan2:ethernet1/2 DHCP Server
Switch2
DHCP Client PC2
Figure 33-1: A DHCP option 82 typical application example
In the above example, layer 2 switches Switch1 and Switch2 are both connected to layer 3
switch Switch3, Switch 3 will transmit the request message from DHCP client to DHCP serer
as DHCP Relay Agent. It will also transmit the reply message from the server to DHCP client to
finish the DHCP protocol procedure. If the DHCP option 82 is disabled, DHCP server cannot
distinguish that whether the DHCP client is from the network connected to Switch1 or Switch2.
So, all the PC terminals connected to Switch1 and Switch2 will get addresses from the public
address pool of the DHCP server. After the DHCP option 82 function is enabled, since the
Switch3 appends the port information of accessing Switch3 to the request message from the
client, the server can tell that whether the client is from the network of Swich1 or Swich2, and
thus can allocate separate address spaces for the two networks, to simplify the management
of networks.
The following is the configuration of Switch3(MAC address is 00:30:4f:02:33:01):
Switch3(Config)#service dhcp
Switch3(Config)#ip dhcp relay information option
Switch3(Config)#ip forward-protocol udp bootps
Switch3(Config)#interface vlan 3
Switch3(Config-if-vlan3)#ip address 192.168.10.222 255.255.255.0
Switch3(Config-if-vlan2)#ip address 192.168.102.2 255.255.255.0
Switch3(Config-if-vlan2)#ip helper 192.168.10.88
Linux ISC DHCP Server supports option 82, its configuration file /etc/dhcpd.con is
ddns-update-style interim;
ignore client-updates;
33-88
class "Switch3Vlan2Class1" {
match if option agent.circuit-id = "Vlan2+Ethernet1/2" and option
agent.remote-id=00:30:4f:02:33:01;
}
class "Switch3Vlan2Class2" {
match if option agent.circuit-id = "Vlan2+Ethernet1/3" and option
agent.remote-id=00:30:4f:02:33:01;
}
subnet 192.168.102.0 netmask 255.255.255.0 {
option routers 192.168.102.2;
option subnet-mask 255.255.255.0;
option domain-name "example.com.cn";
option domain-name-servers 192.168.10.3;
authoritative;
pool {
range 192.168.102.21 192.168.102.50;
default-lease-time 86400; #24 Hours
max-lease-time 172800; #48 Hours
allow members of "Switch3Vlan2Class1";
}
pool {
range 192.168.102.51 192.168.102.80;
default-lease-time 43200; #12 Hours
max-lease-time 86400; #24 Hours
allow members of "Switch3Vlan2Class2";
}
}
Now, the DHCP server will allocate addresses for the network nodes from Switch1 which
are relayed by Switch3 within the range of 192.168.102.21 ~ 192.168.102.50, and allocate
addresses for the network nodes from Switch1 within the range of 192.168.102.51～
192.168.102.80.
33-89
33.4 DHCP Option 82 Troubleshooting
DHCP option 82 is implemented as a sub-function module of DHCP Relay Agent.
Before using it, users should make sure that the DHCP Relay Agent is configured
correctly.
DHCP option 82 needs the DHCP Relay Agent and the DHCP server cooperate to
finish the task of allocating IP addresses. The DHCP server should set allocating
policy correctly depending on the network topology of the DHCP Relay Agent, or,
even the Relay Agent can operate normally, the allocation of addresses will fail.
When there is more than one kind of Relay Agent, please pay attention to the
retransmitting policy of the interface DHCP request messages.
To implement the option 82 function of DHCP Relay Agent, the “debug dhcp relay
packet” command can be used during the operating procedure, including adding the
contents of option 82, the retransmitting policy adopted, the option 82 contents of the
server peeled by the Relay Agent and etc., such information can help users to do
troubleshooting.
To implement the option 82 function of DHCP server, the “debug ip dhcp server
packet” command can be used during the operating procedure to display the
procedure of data packets processing of the server, including displaying the
identified option 82 information of the request message and the option 82
information returned by the reply message.
33-90
Chapter 34 DHCP Option 60 and option
43
34.1 Introduction to DHCP Option 60 and Option 43
DHCP server analyzes DHCP packets from DHCP client. If packets with option 60, it will
decide whether option 43 is returned to DHCP client according to option 60 of packets and
configuration of option 60 and option 43 in DHCP server address pool.
Configure the corresponding option 60 and option 43 in DHCP server address pool:
1. Address pool configured option 60 and option 43 at the same time. The received DHCP
packet with option 60 from DHCP client, if it matches with option 60 of DHCP server address
pool, DHCP client will receive the option 43 configured in the address pool, or else do not
return option 43 to DHCP client.
2. Address pool only configured option 43, it will match with any option 60. If the received
DHCP packet with option 60 from DHCP client, DHCP client will receive the option 43
configured in the address pool.
3. Address pool only configured option 60, it will not return option 43 to DHCP client.
34.2 DHCP Option 60 and Option 43 Configuration
Task List
1. Basic DHCP option 60 and option 43 configuration
Command Explanation
Address Pool Mode
option 60 ascii LINE
Configure option 60 character
string with ascii format in ip
dhcp pool mode.
option 43 ascii LINE
Configure option 43 character
string with ascii format in ip
dhcp pool mode.
option 60 hex WORD Configure option 60 character
34-91
string with hex format in ip
dhcp pool mode.
option 43 hex WORD
Configure option 43 character
string with hex format in ip
dhcp pool mode.
option 60 ip A.B.C.D
Configure option 60 character
string with IP format in ip dhcp
pool mode.
option 43 ip A.B.C.D
Configure option 43 character
string with IP format in ip dhcp
pool mode.
no option 60 Delete the configured option
60 in the address pool mode.
no option 43 Delete the configured option
43 in the address pool mode.
34.3 DHCPv6 Option 60 and Option 43 Example
Figure 34-1: Typical DHCP option 60 and option 43 topology
Fit AP obtains IP address and option 43 attribute by DHCP server to send unicast discovery
request for wireless controller. DHCP server configures option 60 matched with the option 60
of fit ap to return option 43 attribute to FTP AP. The wireless controller addresses of DHCP
option 43 are 192.168.10.5 and 192.168.10.6.
Configuration procedure:
# Configure DHCP server
switch (config)#ip dhcp pool a
switch (dhcp-a-config)#option 60 ascii AP1000
switch (dhcp-a-config)#option 43 hex 0104C0A80A050104C0A80A06
34-92
34-93
34.4 DHCP Option 60 and Option 43 Troubleshooting
If problems occur when configuring DHCP option 60 and option 43, please check whether the
problem is caused by the following reasons:
Check whether service dhcp function is enabled
If the address pool configured option 60, check whether it matches with the option 60
of the packets
Chapter 35 DHCPv6 Options 37, 38
35.1 Introduction to DHCPv6 Options 37, 38
DHCPv6 (Dynamic Host Configuration Protocol for IPv6) is designed for IPv6 address scheme
and is used for assigning IPv6 prefixes, IPv6 addresses and other configuration parameters to
hosts.
When DHCPv6 client wants to request address and configure parameter of DHCPv6 server
from different link, it needs to communicate with server through DHCPv6 relay agent. DHCPv6
message received by relay agent node is reencapsulated to be relay-forward packets and they
are forwarded to the server which sends the relay-reply packets to DHCPv6 relay agent node
in different link, after that, relay agent node restores DHCPv6 message to DHCPv6 client to
finish communication between client and server.
There are some problems when using DHCPv6 relay agent, for example: How to assign IP
address in the fixed range to the specified users? How to avoid illegal DHCPv6 client to forge
IP address exhaust attack triggered by MAC address fields of DHCPv6 packets? How to avoid
illegal DHCPv6 client to trigger deny service attack through using MAC address of other legal
clients? Therefore, IETF set rfc4649 and rfc4580, i.e. DHCPv6 option 37 and option 38 to
solve these problems.
DHCPv6 option 37 and option 38 is similar to DHCP option 82. When DHCPv6 client sends
request packets to DHCPv6 server though DHCPv6 relay agent, if DHCPv6 relay agent
supports option 37 and option 38, they will be added to request packets. For the respond
packets of server, option 37 and option 38 are meaningless and are peeled from the respond
packets. Therefore, the application of option 37 and option 38 is transparent for client.
DHCPv6 server can authenticate identity of DHCPv6 client and DHCPv6 relay device by
option 37 and option 38, assign and manage client address neatly through configuring the
assign policy, prevent DHCPv6 attack availably according to the inclusive client information,
such as forging MAC address fields of DHCPv6 packets to trigger IP address exhaust attack.
Since server can identify multiple request packets from the same access port, it can assign the
address number through policy limit to avoid address exhaust. However, rfc4649 and rfc4580
do not set how to use option 37 and option 38 for DHCPv6 server, users can use it neatly
according to their own demand.
35-1
35.2 DHCPv6 Options 37, 38 Configuration Task List
1. Dhcpv6 snooping option basic functions configuration
2. Dhcpv6 relay option basic functions configuration
3. Dhcpv6 server option basic functions configuration
1.DHCPv6 snooping option basic functions configuration
Command Description
Global Mode
ipv6 dhcp snooping remote-id option
no ipv6 dhcp snooping remote-id option
This command enables
DHCPv6 SNOOPING to
support option 37 option, no
command disables it.
ipv6 dhcp snooping subscriber-id option
no ipv6 dhcp snooping subscriber-id option
This command enables
DHCPv6 SNOOPING to
support option 38 option, no
command disables it.
ipv6 dhcp snooping remote-id policy {drop | keep |
replace}
no ipv6 dhcp snooping remote-id policy
This command is used to
configure the reforwarded
policy of the system when
receiving DHCPv6 packets
with option 37, which can be:
drop, the system simply
discards it with option 37;
keep, the system keeps option
37 unchanged and forwards
the packet to the server;
replace, the system replaces
option 37 of current packet with
its own before forwarding it to
the server. no command
configures the reforwarded
policy of DHCPv6 packets with
option 37 as replace.
ipv6 dhcp snooping subscriber-id policy {drop |
keep | replace}
no ipv6 dhcp snooping subscriber-id policy
This command is used to
configure the reforwarded
policy of the system when
35-2
receiving DHCPv6 packets
with option 38, which can be:
drop, the system simply
discards it with option 38;
keep, the system keeps option
38 unchanged and forwards
the packet to the server;
replace, the system replaces
option 38 of current packet with
its own before forwarding it to
the server. no command
configures the reforwarded
policy of DHCPv6 packets with
option 38 as replace.
ipv6 dhcp snooping subscriber-id select (sp | sv | pv
| spv) delimiter WORD (delimiter WORD |)
no ipv6 dhcp snooping subscriber-id select
delimiter
Configures user configuration
options to generate
subscriber-id, no command
restores to its original default
configuration, i.e. enterprise
number together with vlan
MAC.
ipv6 dhcp snooping subscriber-id select
(sp|sv|pv|spv) delimiter WORD (delimiter WORD |)
no ipv6 dhcp snooping subscriber-id select
delimiter
Configures user configuration
options to generate
subscriber-id. The no
command restores to its
original default configuration,
i.e. vlan name together with
port name.
Port Mode
ipv6 dhcp snooping remote-id <remote-id>
no ipv6 dhcp snooping remote-id
This command is used to set
the form of adding option 37 in
received DHCPv6 request
packets, of which <remote-id>
is the content of remote-id in
user-defined option 37 and it is
a string with a length of less
than 128. The no operation
restores remote-id in option 37
35-3
2. DHCPv6 relay option basic functions configuration
Command Description
Global Mode
ipv6 dhcp relay remote-id option
no ipv6 dhcp relay remote-id option
This command enables the
switch relay to support option
37 and the no form of this
command disables it.
ipv6 dhcp relay subscriber-id option
no ipv6 dhcp relay subscriber-id option
This command enables the
switch relay to support the
option 38, the no form of this
command disables it.
ipv6 dhcp relay remote-id delimiter WORD
no ipv6 dhcp relay remote-id delimiter
Configures user configuration
options to generate remote-id.
The no command restores to
its original default
configuration, i.e. enterprise
number together with vlan
MAC.
ipv6 dhcp relay subscriber-id select (sp | sv | pv | Configures user configuration
to enterprise-number together
with vlan MAC address.
ipv6 dhcp snooping subscriber-id <subscriber-id>
no ipv6 dhcp snooping subscriber-id
This command is used to set
the form of adding option 38 in
received DHCPv6 request
packets, of which
<subscriber-id> is the content
of subscriber-id in user-defined
option 38 and it is a string with
a length of less than 128. The
no operation restores
subscriber-id in option 38 to
vlan name together with port
name such as
"Vlan2+Ethernet1/2".
35-4
spv) delimiter WORD (delimiter WORD |)
no ipv6 dhcp relay subscriber-id select delimiter
options to generate
subscriber-id. The no
command restores to its
original default configuration,
i.e. vlan name together with
port name.
Layer 3 Interface Mode
ipv6 dhcp relay remote-id <remote-id>
no ipv6 dhcp relay remote-id
This command is used to set
the form of adding option 37 in
received DHCPv6 request
packets, of which <remote-id>
is the content of remote-id in
user-defined option 37 and it is
a string with a length of less
than 128. The no operation
restores remote-id in option 37
to enterprise-number together
with vlan MAC address.
ipv6 dhcp relay subscriber-id <subscriber-id>
no ipv6 dhcp relay subscriber-id
This command is used to set
the form of adding option 38 in
received DHCPv6 request
packets, of which
<subscriber-id> is the content
of subscriber-id in user-defined
option 38 and it is a string with
a length of less than 128. The
no operation restores
subscriber-id in option 38 to
vlan name together with port
name such as
"Vlan2+Ethernet1/2".
3. Dhcpv6 server option basic functions configuration
Command Description
Global Mode
ipv6 dhcp server remote-id option
no ipv6 dhcp server remote-id option
This command enables
DHCPv6 server to support the
35-5
identification of option 37, the
no form of this command
disables it.
ipv6 dhcp server subscriber-id option
no ipv6 dhcp server subscriber-id option
This command enables
DHCPv6 server to support the
identification of option 38, the
no form of this command
disables it.
ipv6 dhcp use class
no ipv6 dhcp use class
This command enables
DHCPv6 server to support the
using of DHCPv6 class during
address assignment, the no
form of this command disables
it without removing the relative
DHCPv6 class information that
has been configured.
ipv6 dhcp class <class-name>
no ipv6 dhcp class <class-name>
This command defines a
DHCPv6 class and enters
DHCPv6 class mode, the no
form of this command removes
this DHCPv6 class.
VLAN Interface Mode
ipv6 dhcp server select relay-forw
no ipv6 dhcp server select relay-forw
This command enables the
DHCPv6 server to support
selections when multiple
option 37 or option 38 options
exist and the option 37 and
option 38 of relay-forw in the
innermost layer are selected.
The no operation of it restores
the default configuration, i.e.
selecting option 37 and option
38 of the original packets.
IPv6 DHCP Class Mode
{remote-id [*] <remote-id> [*] | subscriber-id [*]
<subscriber-id> [*]}
no {remote-id [*] <remote-id> [*] | subscriber-id [*]
<subscriber-id> [*]}
This command configures
option 37 and option 38 that
match the class in ipv6 dhcp
class configuration mode.
35-6
DHCPv6 Address Pool Mode
class <class-name>
no class <class-name>
This command associates
class to address pool in
DHCPv6 address pool
configuration mode and enters
class configuration mode in
address pool. Use no
command to remove the link.
address range <start-ip> <end-ip>
no address range <start-ip> <end-ip>
This command is used to set
address range for a DHCPv6
class in DHCPv6 address pool
configuration mode, the no
command is used to remove
the address range. The
prefix/plen form is not
supported.
35-7
35.3 DHCPv6 Options 37, 38 Examples
35.3.1 DHCPv6 Snooping options 37, 38 Example
Switch B
Interface E1/1
Switch A
Interface E1/4 Interface E1/3 Interface E1/2
MAC-CC MAC-AA MAC-BB
Figure 35-1: DHCPv6 Snooping option schematic
As shown in the figure above, Mac-AA, Mac-BB and Mac-CC are normal users, connected to
untrusted interface 1/2, 1/3 and 1/4 respectively, and they get IP 2010:2, 2010:3 and 2010:4
through DHCPv6 Client; DHCPv6 Server is connected to the trusted interface 1/1. Configure
three address assignment policies (CLASS), of which CLASS1 matches option 38, CLASS2
matches option 37 and CLASS3 matches option 37 and option 38. In the address pool
EastDormPool, the requests matched with CLASS1, CLASS2 and CLASS3 will be assigned
an address ranging from 2001:da8:100:1::2 to 2001:da8:100:1::30, from 2001:da8:100:1::31
to 2001:da8:100:1::60 and from 2001:da8:100:1::61 to2001:da8:100:1::100 respectively;
DHCPv6 snooping function is enabled and option 37 and option 38 are configured in Switch
A.
Switch A configuration:
SwitchA(config)#ipv6 dhcp snooping remote-id option
SwitchA(config)#ipv6 dhcp snooping subscriber-id option
SwitchA(config)#int e 1/1
SwitchA(config-if-ethernet1/1)#ipv6 dhcp snooping trust
35-8
SwitchA(config-if-ethernet1/1)#exit
SwitchA(config)#interface vlan 1
SwitchA(config-if-vlan1)#ipv6 address 2001:da8:100:1::1
SwitchA(config-if-vlan1)#exit
SwitchA(config)#interface ethernet 1/1-4
SwitchA(config-if-port-range)#switchport access vlan 1
SwitchA(config-if-port-range)#exit
SwitchA(config)#
Switch B configuration:
SwitchB(config)#service dhcpv6
SwitchB(config)#ipv6 dhcp server remote-id option
SwitchB(config)#ipv6 dhcp server subscriber-id option
SwitchB(config)#ipv6 dhcp pool EastDormPool
SwitchB(dhcpv6-eastdormpool-config)#network-address 2001:da8:100:1::2
2001:da8:100:1::1000
SwitchB(dhcpv6-eastdormpool-config)#dns-server 2001::1
SwitchB(dhcpv6-eastdormpool-config)#domain-name dhcpv6.com
SwitchB(dhcpv6-eastdormpool-config)# excluded-address 2001:da8:100:1::2
SwitchB(dhcpv6-eastdormpool-config)#exit
SwitchB(config)#
SwitchB(config)#ipv6 dhcp class CLASS1
SwitchB(dhcpv6-class-class1-config)#remote-id 00-30-4f-00-00-01 subscriber-id
vlan1+Ethernet1/1
SwitchB(dhcpv6-class-class1-config)#exit
SwitchB(config)#ipv6 dhcp class CLASS2
SwitchB(dhcpv6-class-class2-config)#remote-id 00-30-4f-00-00-01 subscriber-id
vlan1+Ethernet1/2
SwitchB(dhcpv6-class-class2-config)#exit
SwitchB(config)#ipv6 dhcp class CLASS3
SwitchB(dhcpv6-class-class3-config)#remote-id 00-30-4f-00-00-01 subscriber-id
vlan1+Ethernet1/3
SwitchB(dhcpv6-class-class3-config)#exit
SwitchB(config)#ipv6 dhcp pool EastDormPool
SwitchB(dhcpv6-eastdormpool-config)#class CLASS1
SwitchB(dhcpv6-pool-eastdormpool-class-class1-config)#address range
35-9
2001:da8:100:1::3 2001:da8:100:1::30
SwitchB(dhcpv6-pool-eastdormpool-class-class1-config)#exit
SwitchB(dhcpv6-eastdormpool-config)#class CLASS2
SwitchB(dhcpv6-pool-eastdormpool-class-class2-config)#address range
2001:da8:100:1::31 2001:da8:100:1::60
SwitchB(dhcpv6-eastdormpool-config)#class CLASS3
SwitchB(dhcpv6-pool-eastdormpool-class-class3-config)#address range
2001:da8:100:1::61 2001:da8:100:1::100
SwitchB(dhcpv6-pool-eastdormpool-class-class3-config)#exit
SwitchB(dhcpv6-eastdormpool-config)#exit
SwitchB(config)#interface vlan 1
SwitchB(config-if-vlan1)#ipv6 address 2001:da8:100:1::2/64
SwitchB(config-if-vlan1)#ipv6 dhcp server EastDormPool
SwitchB(config-if-vlan1)#exit
SwitchB(config)#
35.3.2 DHCPv6 Relay option37, 38 Example
Example 1:
When deploying IPv6 campus network, DHCPv6 server function of routing device can be used
for IPv6 address allocation if special server is used for uniform allocation and management for
IPv6 address. DHCPv6 server supports both stateful and stateless DHCPv6.
Network topology:
In access layer, layer2 access device Switch1 connects users in dormitory; in first-level
aggregation layer, aggregation device Switch2 is used as DHCPv6 relay agent; in second-level
aggregation layer, aggregation device Switch3 is used as DHCPv6 server and connects with
backbone network or devices in higher aggregation layer; in user side, PCs are generally
loaded with Windows Vista system, thus having DHCPv6 client.
35-10
Figure 35-2: DHCPv6 relay option schematic
Switch 2 configuration:
S2(config)#service dhcpv6
S2(config)#ipv6 dhcp relay remote-id option
S2(config)#ipv6 dhcp relay subscriber-id option
S2(config)#vlan 10
S2(config-vlan10)#int vlan 10
S2(config-if-vlan10)#ipv6 address 2001:da8:1:::2/64
S2(config-if-vlan10)#ipv6 dhcp relay destination 2001:da8:10:1::1
S2(config-if-vlan10)#exit
S2(config)#
35.4 DHCPv6 Options 37, 38 Troubleshooting
Request packets sent by DHCPv6 client are multicast packets received by the
device within its VLAN, if DHCPv6 server wants to receive the packets from client,
DHCPv6 client and DHCPv6 server must be in the same VLAN, otherwise it needs
to use DHCPv6 relay.
35-11
Snooping option37,38 can process one of the following operations for DHCPv6
request packets with option37,38: replace the original option37,38 with its own;
discard the packets with option37,38; do not execute adding, discarding or
forwarding operation. Therefore, please check policy configuration of snooping
option37,38 on second device when obtaining the false address or no address is
obtained according to option37,38.
DHCPv6 server obtains option37,38 of the packets from client by default, if no, it will
obtain option37,38 of the packet sent by relay.
DHCPv6 server only checks whether the first DHCPv6 relay adds option37,38 that
means only option37,38 of the innermost relay-forw is valid in relay packets.
35-12
Chapter 36 DHCP Snooping
Configuration
36.1 Introduction to DHCP Snooping
DHCP Snooping means that the switch monitors the IP-getting process of DHCP CLIENT via
DHCP protocol. It prevents DHCP attacks and illegal DHCP SERVER by setting trusted ports
and untrusted ports. And the DHCP messages from trusted ports can be forwarded without
being verified. In typical settings, trusted ports are used to connect DHCP SERVER or DHCP
RELAY Proxy, and untrusted ports are used to connect DHCP CLINET. The switch will forward
the DCHP request messages from untrusted ports, but not DHCP reply ones. If any DHCP
reply messages is received from a untrusted port, besides giving an alarm, the switch will also
implement designated actions on the port according to settings, such as “shutdown”, or
distributing a “blackhole”. If DHCP Snooping binding is enabled, the switch will save binding
information (including its MAC address, IP address, IP lease, VLAN number and port number)
of each DHCP CLINET on untrusted ports in DHCP snooping binding table With such
information, DHCP Snooping can combine modules like dot1x and ARP, or implement
user-access-control independently.
Defense against Fake DHCP Server: once the switch intercepts the DHCP Server reply
packets（including DHCPOFFER, DHCPACK, and DHCPNAK）, it will alarm and respond
according to the situation（shutdown the port or send Black hole）。
Defense against DHCP over load attacks: To avoid too many DHCP messages attacking
CPU, users should limit the DHCP speed of receiving packets on trusted and non-trusted
ports.
Record the binding data of DHCP: DHCP SNOOPING will record the binding data allocated
by DHCP SERVER while forwarding DHCP messages, it can also upload the binding data to
the specified server to backup it. The binding data is mainly used to configure the dynamic
users of dot1x user based ports. Please refer to the chapter called“dot1x configuration” to find
more about the usage of dot1x use-based mode.
Add binding ARP: DHCP SNOOPING can add static binding ARP according to the binding
data after capturing binding data, thus to avoid ARP cheating.
Add trusted users: DHCP SNOOPING can add trusted user list entries according to the
parameters in binding data after capturing binding data; thus these users can access all
resources without DOT1X authentication.
36-13
Automatic Recovery: A while after the switch shut down the port or send blockhole, it should
automatically recover the communication of the port or source MAC and send information to
Log Server via syslog.
LOG Function: When the switch discovers abnormal received packets or automatically
recovers, it should send syslog information to Log Server.
The Encryption of Private Messages: The communication between the switch and the inner
network security management system TrustView uses private messages. And the users can
encrypt those messages of version 2.
Add authentication option82 Function: It is used with dot1x dhcpoption82 authentication
mode. Different option 82 will be added in DHCP messages according to user’s authentication
status.
36.2 DHCP Snooping Configuration Task Sequence
1. Enable DHCP Snooping
2. Enable DHCP Snooping binding function
3. Enable DHCP Snooping option82 function
4. Set the private packet version
5. Set DES encrypted key for private packets
6. Set helper server address
7. Set trusted ports
8. Enable DHCP Snooping binding DOT1X function
9. Enable DHCP Snooping binding USER function
10. Adding static list entries function
11. Set defense actions
12. Set rate limitation of DHCP messages
13. Enable the debug switch
14. Configure DHCP Snooping option 82 attributes
1. Enable DHCP Snooping
Command Explanation
Globe Mode
ip dhcp snooping enable
no ip dhcp snooping enable Enable or disable the DHCP snooping function.
36-14
2. Enable DHCP Snooping binding
Command Explanation
Globe Mode
ip dhcp snooping binding enable
no ip dhcp snooping binding
enable
Enable or disable the DHCP snooping binding
function.
3. Enable DHCP Snooping binding ARP function
Command Explanation
Globe Mode
ip dhcp snooping binding arp
no ip dhcp snooping binding arp This command is not supported by the switch.
4. Enable DHCP Snooping option82 function
Command Explanation
Globe Mode
ip dhcp snooping information enable
no ip dhcp snooping information
enable
Enable/disable DHCP Snooping option 82
function.
5. Set the private packet version
Command Explanation
Globe Mode
ip user private packet version two
no ip user private packet version twoTo configure/delete the private packet version.
6. Set DES encrypted key for private packets
Command Explanation
Globe Mode
enable trustview key 0/7 <password>
no enable trustview key
To configure/delete DES encrypted key for
private packets.
36-15
7. Set helper server address
Command Explanation
Globe Mode
ip user helper-address A.B.C.D
[port <udpport>] source <ipAddr>
(secondary|)
no ip user helper-address
(secondary|)
Set or delete helper server address.
8. Set trusted ports
Command Explanation
Port Mode
ip dhcp snooping trust
no ip dhcp snooping trust
Set or delete the DHCP snooping trust attributes
of ports.
9. Enable DHCP SNOOPING binding DOT1X function
Command Explanation
Port Mode
ip dhcp snooping binding dot1x
no ip dhcp snooping binding dot1x
Enable or disable the DHCP snooping binding
dot1x function.
10. Enable or disable the DHCP SNOOPING binding USER function
Command Explanation
Port Mode
ip dhcp snooping binding
user-control
no ip dhcp snooping binding
user-control
Enable or disable the DHCP snooping binding
user function.
36-16
11. Add static binding information
Command Explanation
Globe Mode
ip dhcp snooping binding user
<mac> address <ipAddr>
interface (ethernet|) <ifname>
no ip dhcp snooping binding user
<mac> interface (ethernet|)
<ifname>
Add/delete DHCP snooping static binding list
entries.
12. Set defense actions
Command Explanation
Port Mode
ip dhcp snooping action
{shutdown|blackhole} [recovery
<second>]
no ip dhcp snooping action
Set or delete the DHCP snooping automatic
defense actions of ports.
13. Set rate limitation of data transmission
Command Explanation
Globe Mode
ip dhcp snooping limit-rate <pps>
no ip dhcp snooping limit-rate
Set rate limitation of the transmission of DHCP
snooping messages.
14. Enable the debug switch
Command Explanation
Admin Mode
debug ip dhcp snooping packet
debug ip dhcp snooping event
debug ip dhcp snooping update
debug ip dhcp snooping binding
Please refer to the chapter on system
troubleshooting.
36-17
15. Configure DHCP Snooping option 82 attributes
Command Explanation
Globe Mode
ip dhcp snooping information
option subscriber-id format {hex |
acsii | vs-hp}
This command is used to set subscriber-id
format of DHCP snooping option82.
ip dhcp snooping information
option remote-id {standard |
<remote-id>}
no ip dhcp snooping information
option remote-id
Set the suboption2 (remote ID option) content of
option 82 added by DHCP request packets (they
are received by the port). The no command sets
the additive suboption2 (remote ID option)
format of option 82 as standard.
ip dhcp snooping information
option delimiter [colon | dot | slash
| space]
no ip dhcp snooping information
option delimiter
Set the delimiter of each parameter for
suboption of option82 in global mode, no
command restores the delimiter as slash.
ip dhcp snooping information
option self-defined remote-id
{hostname | mac | string WORD}
no ip dhcp snooping information
option self-defined remote-id
Set creation method for option82, users can
define the parameters of remote-id suboption by
themselves.
ip dhcp snooping information
option self-defined remote-id
format [ascii | hex]
Set self-defined format of remote-id for snooping
option82.
ip dhcp snooping information
option self-defined subscriber-id
{vlan | port | id (switch-id (mac |
hostname)| remote-mac) | string
WORD}
no ip dhcp snooping information
option type self-defined
subscriber-id
Set creation method for option82, users can
define the parameters of circute-id suboption by
themselves.
ip dhcp snooping information
option self-defined subscriber-id
format [ascii | hex]
Set self-defined format of circuit-id for snooping
option82.
Port mode
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ip dhcp snooping information
option subscriber-id {standard |
<circuit-id>}
no ip dhcp snooping information
option subscriber-id
Set the suboption1 (circuit ID option) content of
option 82 added by DHCP request packets (they
are received by the port). The no command sets
the additive suboption1 (circuit ID option) format
of option 82 as standard.
Command Explanation
Globe Mode
ip dhcp snooping information
option allow-untrusted (replace|)
no ip dhcp snooping information
option allow-untrusted (replace|)
This command is used to set that allow
untrusted ports of DHCP snooping to receive
DHCP packets with option82 option. When the
"replace" is setting, the potion82 option is
allowed to replace. When disabling this
command, all untrusted ports will drop DHCP
packets with option82 option.
36.3 DHCP Snooping Typical Application
Figure 36-1: Sketch Map of TRUNK
As showed in the above chart, Mac-AA device is the normal user, connected to the non-trusted
port 1/1 of the switch. It operates via DHCP Client, IP 1.1.1.5; DHCP Server and GateWay are
connected to the trusted ports 1/11 and 1/12 of the switch; the malicious user Mac-BB is
connected to the non-trusted port 1/10, trying to fake a DHCP Server（by sending DHCPACK）.
36-19
Setting DHCP Snooping on the switch will effectively detect and block this kind of network
attack.
Configuration sequence is:
switch#
switch#config
switch(config)#ip dhcp snooping enable
switch(config)#interface ethernet 1/11
switch(Config-Ethernet1/11)#ip dhcp snooping trust
switch(Config-Ethernet1/11)#exit
switch(config)#interface ethernet 1/12
switch(Config-Ethernet1/12)#ip dhcp snooping trust
switch(Config-Ethernet1/12)#exit
switch(config)#interface ethernet 1/1-10
switch(Config-Port-Range)#ip dhcp snooping action shutdown
switch(Config-Port-Range)#
36.4 DHCP Snooping Troubleshooting Help
36.4.1 Monitor and Debug Information
The “debug ip dhcp snooping” command can be used to monitor the debug information.
36.4.2 DHCP Snooping Troubleshooting Help
If there is any problem happens when using DHCP Snooping function, please check if the
problem is caused by the following reasons:
Check that whether the global DHCP Snooping is enabled;
If the port does not react to invalid DHCP Server packets, please check that whether
the port is set as a non-trusted port of DHCP Snooping.
36-20
Chapter 37 DHCP Snooping Option 82
Configuration
37.1 Introduction to DHCP Snooping Option 82
DHCP option 82 is the Relay Agent Information Option, its option code is 82. DHCP option 82
is aimed at strengthening the security of DHCP servers and improving the IP address
configuration policy. Switch obtain DHCP request packets(include DHCPDISCOVER,
DHCPREQUEST, DHCPINFORM and DHCPRELEASE), DHCP SNOOPING is added to
option 82 by request packets (including the client’s physical access port, the access device ID
and other information), to the DHCP request message from the client then forwards the
message to DHCP server. When the DHCP server which supports the option 82 function
receives the message, it will allocate an IP address and other configuration information for the
client according to preconfigured policies and the option 82 information in the message. At the
same time, DHCP server can identify all the possible DHCP attack messages according to the
information in option 82 and defend against them. DHCP SNOOPING will peel the option 82
from the reply messages it receives, and forward the reply message to the specified port of the
network access device. The application of DHCP option 82 is transparent for the client.
37.1.1 DHCP Option 82 Message Structure
A DHCP message can have several option segments; option 82 is one of them. It has to be
placed after other options but before option 255. The following is its format:
Code: represents the sequence number of the relay agent information option, the option 82 is
called so because RFC3046 is defined as 82.
Len: the number of bytes in Agent Information Field, not including the two bytes in Code
segment and Len segment.
Option 82 can have several sub-options, and need at least one sub-option. RFC3046 defines
the following two sub-options, whose formats are showed as follows:
37-21
SubOpt: the sequence number of sub-option, the sequence number of Circuit ID sub-option is
1, the sequence number of Remote ID sub-option is 2.
Len: the number of bytes in Sub-option Value, not including the two bytes in SubOpt segment
and Len segment.
37.1.2 DHCP Snooping Option 82 Working Mechanism
DHCP SNOOPING
DHCP option 82 flow chart
If the DHCP SNOOPING supports option 82, the DHCP client should go through the following
four steps to get its IP address from the DHCP server: discover, offer, select and acknowledge.
The DHCP protocol follows the procedure below:
1）DHCP client sends a request broadcast message while initializing. This request message
does not have option 82.
2）DHCP SNOOPING will add the option 82 to the end of the request message it receives, and
perform layer 2 forwarding. By default, the sub-option 1 of option 82 (Circuit ID) is the interface
information of the switch connected to the DHCP client (VLAN name and physical port name).
The sub-option 2 of option 82(Remote ID) is the CPU MAC address of the switch.
3）After receiving the DHCP request message, the DHCP server will allocate IP address and
other information for the client according to the information and preconfigured policy in the
DHCP Request DHCP Request Option82
DHCP Reply
Option82DHCP Reply
DHCP Client DHCP Server
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option segment of the message. Then it will forward the reply message with DHCP
configuration information and option 82 information to DHCP SNOOPING.
4）DHCP SNOOPING will peel the option 82 information from the replay message sent by
DHCP server, then the message with DHCP configuration information to perform layer 2
forwarding.
37.2 DHCP Snooping Option 82 Configuration Task
List
1. Enable DHCP SNOOPING
2. Enable DHCP Snooping binding function
3. Enable DHCP Snooping option 82 binding function
4. Configure trusted ports
1. Enable DHCP SNOOPING
Command Explanation
Global Mode
ip dhcp snooping enable
no ip dhcp snooping enable
Enable or disable DHCP SNOOPING
function.
2. Enable DHCP Snooping binding function
Command Explanation
Global Mode
ip dhcp snooping binding enable
no ip dhcp snooping binding enable
Enable or disable DHCP SNOOPING
binding function.
3. Enable DHCP Snooping option 82 function
Command Explanation
Global Mode
ip dhcp snooping information enable
no ip dhcp snooping information enable
Enable or disable DHCP SNOOPING
option 82 function.
4. Configure trusted ports
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Command Explanation
Port Mode
ip dhcp snooping trust
no ip dhcp snooping trust
Set or delete DHCP SNOOPING trust
attribute of ports.
37.3 DHCP Snooping Option 82 Application Examples
DHCP Client PC1
Switch1
Vlan1:eth1/3
DHCP Server
Figure 37-1: DHCP option 82 typical application example
In the above example, layer 2 Switch1 will transmit the request message from DHCP client to
DHCP serer through enable DHCP Snooping. It will also transmit the reply message from the
server to DHCP client to finish the DHCP protocol procedure. After the DHCP SNOOPING
option 82 function is enabled, the Switch1 appends the port information of accessing Switch1
to the request message from the client by option 82.
The following is the configuration of Switch1(MAC address is 00-30-4f-02-33-01):
Switch1(config)#ip dhcp snooping enable
Switch1(config)#ip dhcp snooping binding enable
Switch1(config)# ip dhcp snooping information enable
Switch1(Config-If-Ethernet1/12)#ip dhcp snooping trust
Linux ISC DHCP Server supports option 82, its configuration file /etc/dhcpd.conf is
ddns-update-style interim;
ignore client-updates;
class "Switch1Vlan1Class1" {
match if option agent.circuit-id = "Vlan1+Ethernet1/3" and option
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agent.remote-id=00:30:4f:02:33:01;
}
subnet 192.168.102.0 netmask 255.255.255.0 {
option routers 192.168.102.2;
option subnet-mask 255.255.255.0;
option domain-name "example.com.cn";
option domain-name-servers 192.168.10.3;
authoritative;
pool {
range 192.168.102.51 192.168.102.80;
default-lease-time 43200; #12 Hours
max-lease-time 86400; #24 Hours
allow members of "Switch1Vlan1Class1";
}
}
Now, the DHCP server will allocate addresses for the network nodes from Switch1 within
the range of 192.168.102.51 ~ 192.168.102.80.
37.4 DHCP Snooping Option 82 Troubleshooting
To implement the option 82 function of DHCP SNOOPING, the “debug ip dhcp
snooping packet” command can be used during the operating procedure, including
adding the option 82 information of the request message, the option 82 information
peeled by the reply message.
37-25
Chapter 38 IPv4 Multicast Protocol
38.1 IPv4 Multicast Protocol Overview
This chapter will give an introduction to the configuration of IPv4 Multicast Protocol.
38.1.1 Introduction to Multicast
Various transmission modes can be adopted when the destination of packet (including data,
sound and video) transmission is the minority users in the network. One way is to use Unicast
mode, i.e. to set up a separate data transmission path for each user; or, to use Broadcast
mode, which is to send messages to all users in the network, and they will receive the
Broadcast messages no matter they need or not. For example, if there are 200 users in a
network who want to receive the same packet, then the traditional solution is to send this
packet for 200 times separately via Unicast to guarantee the users who need the data can get
all data wanted, or send the data in the entire domain via Broadcast. Transferring the data in
the whole range of network .The users who need these data can get directly from the network.
Both modes waste a great deal of valuable bandwidth resource, and furthermore, Broadcast
mode goes against the security and secrecy.
The emergence of IP Multicast technology solved this problem in time. The Multicast source
only sends out the message once, Multicast Routing Protocol sets up tree-routing for Multicast
data packet, and then the transferred packet just starts to be duplicated and distributed in the
bifurcate crossing as far as possible. Thus the packet can be sent to every user who needs it
accurately and effectively.
It should be noticed that it is not necessary for Multicast source to join in Multicast group. It
sends data to some Multicast groups, but it is not necessarily a receiver of the group itself.
There can be more than one source sending packets to a Multicast group simultaneously.
There may exist routers in the network which do not support Multicast, but a Multicast router
can encapsulate the Multicast packets into Unicast IP packets with tunnel mode to send them
to the Multicast router next to it, which will take off the Unicast IP header and continue the
Multicast transmission process, thus a big alteration of network structure is avoided. The
primary advantages of Multicast are:
1. Enhance efficiency: reduce network traffic, lighten the load of server and CPU
38-26
2. Optimize performance: reduce redundant traffic
3. Distributed application: Enable Multipoint Application
38.1.2 Multicast Address
The destination address of Multicast message uses class D IP address with range from
224.0.0.0 to 239.255.255.255. D class address can not appear in the source IP address field
of an IP message. In the process of Unicast data transmission, the transmission path of a data
packet is from source address routing to destination address, and the transmission is
performed with hop-by-hop principle. However, in IP Multicast environment, the destination
addresses is a group instead of a single one, they form a group address. All message
receivers will join in a group, and once they do, the data flowing to the group address will be
sent to the receivers immediately and all members in the group will receive the data packets.
The members in a Multicast group are dynamic, the hosts can join and leave the Multicast
group at any time.
Multicast group can be permanent or temporary. Some of the Multicast group addresses are
assigned officially; they are called Permanent Multicast Group. Permanent Multicast Group
keeps its IP address fixed but its member structure can vary within. The member amount of
Permanent Multicast Group can be arbitrary, even zero. The IP Multicast addresses which are
not kept for use by Permanent Multicast Group can be utilized by temporary Multicast groups.
224.0.0.0 ～ 224.0.0.255 are reserved Multicast addresses (Permanent Group Address),
address 224.0.0.0 is reserved but not assigned, and other addresses are used by Routing
Protocol; 224.0.1.0～238.255.255.255 are Multicast addresses available to users（Temporary
Group Address ） and are valid in the entire domain of the network; 239.0.0.0 ～
239.255.255.255 are local management Multicast addresses, which are valid only in specific
local domain. Frequently used reserved multicast address list is as follows:
Benchmark address (reserved)
224.0.0.1 Address of all hosts
224.0.0.2 Address of all Multicast Routers
224.0.0.3 Unassigned
224.0.0.4 DVMRP Router
224.0.0.5 OSPF Router
224.0.0.6 OSPF DR
224.0.0.7 ST Router
224.0.0.8 ST host
224.0.0.9 RIP-2 Router
224.0.0.10 IGRP Router
38-27
224.0.0.11 Active Agent
224.0.0.12 DHCP Server/Relay Agent
224.0.0.13 All PIM Routers
224.0.0.14 RSVP Encapsulation
224.0.0.15 All CBT Routers
224.0.0.16 Specified SBM
224.0.0.17 All SBMS
224.0.0.18 VRRP
224.0.0.22 IGMP
When Ethernet transmits Unicast IP messages, the destination MAC address it uses is the
receiver’s MAC address. But in transmitting Multicast packets, the transmission destination is
not a specific receiver any more, but a group with uncertain members, thus Multicast MAC
address is used. Multicast MAC address is corresponding to Multicast IP address. It is
prescribed in IANA (Internet Assigned Number Authority) that the higher 25 bits in Multicast
MAC address is 0x01005e, and the lower 23bits in MAC address is the lower 23bits in
Multicast IP address.
Since only 23bits out of the lower 28bits in IP Multicast address are mapped into MAC address,
therefore there are 32 IP Multicast addresses which are mapped into the same MAC address.
38.1.3 IP Multicast Packet Transmission
In Multicast mode, the source host sends packets to the host group indicated by the Multicast
group address in the destination address field of IP data packet. Unlike Unicast mode,
Multicast data packet must be forwarded to a number of external interfaces to be sent to all
receiver sites in Multicast mode, thus Multicast transmission procedure is more complicated
than Unicast transmission procedure.
In order to guarantee that all Multicast packets get to the router via the shortest path, the
receipt interface of the Multicast packet must be checked in some certain way based on
Unicast router table; this checking mechanism is the basis for most Multicast Routing Protocol
to forward in Multicast mode --- RPF (Reverse Path Forwarding) check. Multicast router makes
use of the impressed packet source address to query Unicast Router Table or independent
Multicast Router Table to determine if the packet ingress interface is on the shortest path from
receipt site to source address. If shortest path Tree is used, then the source address is the
address of source host which sends Multicast Data Packets; if Shared Tree is used, then the
source address is the address of the root of the Shared-Tree. When Multicast data packet gets
to the router, if RPF check passes, then the data packet is forwarded according to Multicast
forward item, and the data packet will be discarded else wise.
38-28
38.1.4 IP Multicast Application
IP Multicast technology has effectively solved the problem of sending in single point and
receiving in multipoint. It has achieved the effective data transmission from a point to multiple
points, saved a great deal of network bandwidth and reduced network load. Making use of the
Multicast property of network, some new value-added operations can be supplied conveniently.
In Information Service areas such as online living broadcast, network TV, remote education,
remote medicine, real time video/audio meeting, the following applications may be supplied:
1) Application of Multimedia and Streaming Media
2) Data repository, finance application (stock) etc
3) Any data distribution application of “one point to multiple points”
In the situation of more and more multimedia operations in IP network, Multicast has
tremendous market potential and Multicast operation will be generalized and popularized.
38.2 DCSCM
38.2.1 Introduction to DCSCM
DCSCM (Destination control and source control multicast) technology mainly includes three
aspects, i.e. Multicast Packet Source Controllable, Multicast User Controllable and
Service-Oriented Priority Strategy Multicast.
The Multicast Packet Source Controllable technology of Security Controllable Multicast
technology is mainly processed in the following manners:
1． On the edge switch, if source under-control multicast is configured, then only multicast
data from specified group of specified source can pass.
2． For RP switch in the core of PIM-SM, for REGISTER information out of specified
source and specified group, REGISTER_STOP is transmitted directly and table entry
is not allowed to set up. (This task is implemented in PIM-SM model).
The implement of Multicast User Controllable technology of Security Controllable Multicast
technology is based on the control over IGMP report message sent out by the user, thus the
model being controlled is IGMP snooping and IGMPmodel, of which the control logic includes
the following three, i.e. to take control based on VLAN+MAC address transmitting packets, to
take control based on IP address of transmitting packets and to take control based on the port
where messages enter, in which IGMP snooping can use the above three methods to take
control simultaneously, while since IGMP model is located at layer 3, it only takes control over
the IP address transmitting packets.
38-29
The Service-Oriented Priority Strategy Multicast of Security Controllable technology adopts the
following mode: for multicast data in limit range, set the priority specified by the user at the
join-in end so that data can be sent in a higher priority on TRUNK port, consequently
guarantee the transmission is processed in user-specified priority in the entire network.
38.2.2 DCSCM Configuration Task List
1． Source Control Configuration
2． Destination Control Configuration
3． Multicast Strategy Configuration
1． Source Control Configuration
Source Control Configuration has three parts, of which the first is to enable source control. The
command of source control is as follows:
Command Explanation
Global Mode
[no] ip multicast source-control
(Required)
Enable source control globally, the “no ip
multicast source-control” command disables
source control globally. It is noticeable that, after
enabling source control globally, all multicast
packets are discarded by default. All source
control configuration can not be processed until
that it is enabled globally, while source control
can not be disabled until all configured rules are
disabled.
The next is to configure the rule of source control. It is configured in the same manner as for
ACL, and uses ACL number of 5000-5099, every rule number can be used to configure 10
rules. It is noticeable that these rules are ordered, the front one is the one which is configured
the earliest. Once the configured rules are matched, the following rules won’t take effect, so
rules of globally allow must be put at the end. The commands are as follows:
Command Explanation
Global Mode
38-30
[no] access-list <5000-5099>
{deny|permit} ip {{<source>
<source-wildcard>}|{host-source
<source-host-ip>}|any-source}
{{<destination>
<destination-wildcard>}|{host-desti
nation
<destination-host-ip>}|any-destinat
ion}
The rule used to configure source control. This
rule does not take effect until it is applied to
specified port. Using the NO form of it can delete
specified rule.
The last is to configure the configured rule to specified port.
Note: If the rules being configured will occupy the table entries of hardware, configuring too
many rules will result in configuration failure caused by bottom table entries being full, so we
suggest user to use the simplest rules if possible. The configuration rules are as follows:
Command Explanation
Port Mode
[no] ip multicast source-control
access-group <5000-5099>
Used to configure the rules source control uses
to port, the NO form cancels the configuration.
2． Destination Control Configuration
Like source control configuration, destination control configuration also has three steps.
First, enable destination control globally. Since destination control need to prevent
unauthorized user from receiving multicast data, the switch won’t broadcast the multicast data
it received after configuring global destination control. Therefore, It should be avoided to
connect two or more other Layer 3 switches in the same VLAN on a switch on which
destination control is enabled. The configuration commands are as follows:
Command Explanation
Global Mode
[no] multicast destination-control
（required）
Globally enable destination control.
The no operation of this command will
globally disable destination control. All
of the other configuration can only
take effect after globally enabled. The
next is configuring destination control
rules, which are similar.
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Next is to configure destination control rule. It is similar to source control, except to use ACL
No. of 6000-7999.
Command Explanation
Global Mode
[no] access-list <6000-7999> {deny|permit} ip
{{<source> <source-wildcard>}|{host-source
<source-host-ip>{range<2-65535>|}}|any-sou
rce} {{<destination>
<destination-wildcard>}|{host-destination
<destination-host-ip>{range<2-255>|}}|any-d
estination}
The rule used to configure destination
control. This rule does not take effect
until it is applied to source IP or
VLAN-MAC and port. Using the NO
form of it can delete specified rule.
The last is to configure the rule to specified source IP, source VLAN MAC or specified port. It is
noticeable that, due to the above situations, these rules can only be used globally in enabling
IGMP-SNOOPING. And if IGMP-SNOOPING is not enabled, then only source IP rule can be
used under IGMP Protocol. The configuration commands are as follows:
Command Explanation
Port Mode
[no] ip multicast destination-control
access-group <6000-7999>
Used to configure the rules destination
control uses to port, the NO form
cancels the configuration.
Global Mode
[no] ip multicast destination-control
<1-4094> <macaddr> access-group
<6000-7999>
Used to configure the rules destination
control uses to specify VLAN-MAC, the
NO form cancels the configuration.
[no] ip multicast destination-control
<IPADDRESS/M> access-group
<6000-7999>
Used to configure the rules destination
control uses to specified IP address/net
mask, the NO form cancels the
configuration.
3． Multicast Strategy Configuration
Multicast Strategy uses the manner of specifying priority for specified multicast data to achieve
and guarantee the effects the specific user requires. It is noticeable that multicast data can not
get a special care all along unless the data are transmitted at TRUNK port. The configuration is
very simple, it has only one command, i.e. to set priority for the specified multicast. The
38-32
commands are as follows:
Command Explanation
Global Mode
[no] ip multicast policy <IPADDRESS/M>
<IPADDRESS/M> cos <priority>
Configure multicast strategy, specify
priority for sources and groups in
specific range, and the range is <0-7>.
38.2.3 DCSCM Configuration Examples
1． Source Control
In order to prevent an Edge Switch from putting out multicast data ad asbitsium, we configure
Edge Switch so that only the switch at port Ethernet1/5 is allowed to transmit multicast, and the
data group must be 225.1.2.3. Also, switch connected up to port Ethernet1/10 can transmit
multicast data without any limit, and we can make the following configuration.
EC(config)#access-list 5000 permit ip any host 225.1.2.3
EC(config)#access-list 5001 permit ip any any
EC(config)#ip multicast source-control
EC(config)#interface ethernet1/5
EC(Config-If-Ethernet1/5)#ip multicast source-control access-group 5000
EC(config)#interface ethernet1/10
EC(Config-If-Ethernet1/10)#ip multicast source-control access-group 5001
2． Destination Control
We want to limit users with address in 10.0.0.0/8 network segment from entering the group of
238.0.0.0/8, so we can make the following configuration:
Firstly enable IGMP snooping in the VLAN it is located (Here it is assumed to be in VLAN2)
EC(config)#ip igmp snooping
EC(config)#ip igmp snooping vlan 2
After that, configure relative destination control access-list, and configure specified IP address
to use that access-list.
Switch(config)#access-list 6000 deny ip any 238.0.0.0 0.255.255.255
Switch(config)#access-list 6000 permit ip any any
Switch(config)#multicast destination-control
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Switch(config)#ip multicast destination-control 10.0.0.0/8 access-group 6000
In this way, users of this network segment can only join groups other than 238.0.0.0/8.
3． Multicast strategy
Server 210.1.1.1 is distributing important multicast data on group 239.1.2.3, we can configure
on its join-in switch as follows:
Switch(config)#ip multicast policy 210.1.1.1/32 239.1.2.3/32 cos 4
In this way, the multicast stream will have a priority of value 4 (Usually this is pretty higher, the
higher possible one is protocol data; if higher priority is set, when there is too many multicast
data, it might cause abnormal behavior of the switch protocol) when it gets to other switches
through this switch.
38.2.4 DCSCM Troubleshooting
The effect of DCSCM module itself is similar to ACL, and the problems occurred are usually
related to improper configuration. Please read the descriptions above carefully. If you still can
not determine the cause of the problem, please send your configurations and the effects you
expect to the after-sale service staff of our company.
38.3 IGMP Snooping
38.3.1 Introduction to IGMP Snooping
IGMP (Internet Group Management Protocol) is a protocol used in IP multicast. IGMP is used
by multicast enabled network device (such as a router) for host membership query, and by
hosts that are joining a multicast group to inform the router to accept packets of a certain
multicast address. All those operations are done through IGMP message exchange. The
router will use a multicast address (224.0.0.1) that can address to all hosts to send an IGMP
host membership query message. If a host wants to join a multicast group, it will reply to the
multicast address of that a multicast group with an IGMP host membership reports a message.
IGMP Snooping is also referred to as IGMP listening. The switch prevents multicast traffic from
flooding through IGMP Snooping, multicast traffic is forwarded to ports associated to multicast
devices only. The switch listens to the IGMP messages between the multicast router and hosts,
and maintains multicast group forwarding table based on the listening result, and can then
38-34
decide to forward multicast packets according to the forwarding table.
Switch provides IGMP Snooping and is able to send a query from the switch so that the user
can use switch in IP multicast.
38.3.2 IGMP Snooping Configuration Task List
1. Enable IGMP Snooping
2. Configure IGMP Snooping
1. Enable IGMP Snooping
Command Explanation
Global Mode
ip igmp snooping
no ip igmp snooping
Enables IGMP Snooping. The no operation
disables IGMP Snooping function.
2. Configure IGMP Snooping
Command Explanation
Global Mode
ip igmp snooping vlan <vlan-id>
no ip igmp snooping vlan <vlan-id>
Enables IGMP Snooping for specified VLAN.
The no operation disables IGMP Snooping for
specified VLAN.
ip igmp snooping proxy
no ip igmp snooping proxy
Enable IGMP Snooping proxy function, the no
command disables the function.
ip igmp snooping vlan < vlan-id > limit
{group <g_limit> | source <s_limit>}
no ip igmp snooping vlan < vlan-id > limit
Configure the max. group count of vlan and
the max. source count of every group. The “no
ip igmp snooping vlan <vlan-id> limit”
command cancels this configuration.
ip igmp snooping vlan <1-4094> interface
(ethernet | port-channel|) IFNAME limit
{group <1-65535>| source <1-65535>}
strategy (replace | drop)
no ip igmp snooping vlan <1-4094>
interface (ethernet | port-channel|)
Configure the number of groups which are
allowed joining and the maximum of the
source in each group under the IGMP
Snooping port. Configure the strategy when it
is up to the upper limit, including “replace” and
“drop”. No command configures as “no
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IFNAME limit group source strategy limitation”.
ip igmp snooping vlan <vlan-id>
l2-general-querier
no ip igmp snooping vlan <vlan-id>
l2-general-querier
Set this vlan to layer 2 general querier. It is
recommended to configure a layer 2 general
querier on a segment. The “no ip igmp
snooping vlan <vlan-id>
l2-general-querier”command cancels this
configuration.
ip igmp snooping vlan <vlan-id>
l2-general-querier-version <version>
Configure the version number of a general
query from a layer 2 general querier.
ip igmp snooping vlan <vlan-id>
l2-general-querier-source <source>
Configure the source address of a general
query from a layer 2 general querier.
ip igmp snooping vlan <vlan-id>
mrouter-port interface <interface –name>
no ip igmp snooping vlan <vlan-id>
mrouter-port interface <interface –name>
Configure static mrouter port of vlan. The no
form of the command cancels this
configuration.
ip igmp snooping vlan <vlan-id>
mrouter-port learnpim
no ip igmp snooping vlan <vlan-id>
mrouter-port learnpim
Enable the function that the specified VLAN
learns mrouter-port (according to pim
packets), the no command will disable the
function.
ip igmp snooping vlan <vlan-id> mrpt
<value >
no ip igmp snooping vlan <vlan-id> mrpt
Configure this survive time of mrouter port.
The “no ip igmp snooping vlan <vlan-id>
mrpt” command restores the default value.
ip igmp snooping vlan <vlan-id>
query-interval <value>
no ip igmp snooping vlan <vlan-id>
query-interval
Configure this query interval. The “no ip igmp
snooping vlan <vlan-id> query-interval”
command restores the default value.
ip igmp snooping vlan <vlan-id>
immediately-leave
no ip igmp snooping vlan <vlan-id>
immediately-leave
Enable the IGMP fast leave function for the
specified VLAN: the “no ip igmp snooping
vlan <vlan-id> immediate-leave” command
disables the IGMP fast leave function.
ip igmp snooping vlan <vlan-id>
query-mrsp <value>
no ip igmp snooping vlan <vlan-id>
query-mrsp
Configure the maximum query response
period. The “no ip igmp snooping vlan
<vlan-id> query-mrsp” command restores to
the default value.
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ip igmp snooping vlan <vlan-id>
query-robustness <value>
no ip igmp snooping vlan <vlan-id>
query-robustness
Configure the query robustness. The “no ip
igmp snooping vlan <vlan-id>
query-robustness” command restores to the
default value.
ip igmp snooping vlan <vlan-id>
suppression-query-time <value>
no ip igmp snooping vlan <vlan-id>
suppression-query-time
Configure the suppression query time. The
“no ip igmp snooping vlan <vlan-id>
suppression-query-time” command
restores to the default value.
ip igmp snooping vlan <vlan-id>
static-group <A.B.C.D> [source
<A.B.C.D>] interface [ethernet |
port-channel] <IFNAME>
no ip igmp snooping vlan <vlan-id>
static-group <A.B.C.D> [source
<A.B.C.D>] interface [ethernet |
port-channel] <IFNAME>
Configure static-group on specified port of the
VLAN. The no form of the command cancels
this configuration.
ip igmp snooping vlan <vlan-id> report
source-address <A.B.C.D>
no ip igmp snooping vlan <vlan-id>
report source-address
Configure forwarding IGMP packet source
address, The no operation cancels the packet
source address.
ip igmp snooping vlan <vlan-id>
specific-query-mrsp <value>
no ip igmp snooping vlan <vlan-id>
specific-query-mrspt
Configure the maximum query response time
of the specific group or source, the no
command restores the default value.
38.3.3 IGMP Snooping Examples
Scenario 1: IGMP Snooping function
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Multicast router
Group 1
IGMP Snooping
Multicast port
Group 1 Group 1 Group 2
Multicast Server 1 Multicast Server 2
Figure 38-1: Enabling IGMP Snooping function
Example: As shown in the above figure, a VLAN 100 is configured in the switch and includes
ports 1, 2, 6, 10 and 12. Four hosts are connected to port 2, 6, 10 and 12 respectively and the
multicast router is connected to port 1. As IGMP Snooping is disabled by default either in the
switch or in the VLANs, If IGMP Snooping should be enabled in VLAN 100, the IGMP
Snooping should be first enabled for the switch in Global Mode and in VLAN 100 and set port 1
of VLAN 100 to be the mrouter port.
The configuration steps are listed below:
Switch(config)#ip igmp snooping
Switch(config)#ip igmp snooping vlan 100
Switch(config)#ip igmp snooping vlan 100 mrouter interface ethernet 1/1
Multicast Configuration
Suppose two programs are provided in the Multicast Server using multicast address Group1
and Group2, three of four hosts running multicast applications are connected to port 2, 6, 10
plays program1, while the host is connected to port 12 plays program 2.
IGMP Snooping listening result:
The multicast table built by IGMP Snooping in VLAN 100 indicates ports 1, 2, 6, 10 in Group1
and ports 1, 12 in Group2.
All the four hosts can receive the program of their choice: ports 2, 6, 10 will not receive the
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traffic of program 2 and port 12 will not receive the traffic of program 1.
Scenario 2: L2-general-querier
Multicast
Server Group 1 Group 2
Switch A IGMP Snooping L2 general querier
Multicast port Switch B IGMP Snooping
Group 1 Group 1 Group 1 Group 2
Figure 38-2: The switches as IGMP Queries
The configuration of Switch2 is the same as the switch in scenario 1, SwitchA takes the place
of Multicast Router in scenario 1. Let’s assume VLAN 60 is configured in SwitchA, including
ports 1, 2, 10 and 12. Port 1 connects to the multicast server, and port 2 connects to Switch2.
In order to send Query at regular interval, IGMP query must enabled in Global mode and in
VLAN60.
The configuration steps are listed below:
SwitchA#config
SwitchA(config)#ip igmp snooping
SwitchA(config)#ip igmp snooping vlan 60
SwitchA(config)#ip igmp snooping vlan 60 L2-general-querier
SwitchB#config
SwitchB(config)#ip igmp snooping
SwitchB(config)#ip igmp snooping vlan 100
SwitchB(config)#ip igmp snooping vlan 100 mrouter interface ethernet 1/1
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Multicast Configuration
The same as scenario 1
IGMP Snooping listening result:
Similar to scenario 1
38.3.4 IGMP Snooping Troubleshooting
On IGMP Snooping function configuration and usage, IGMP Snooping might not run properly
because of physical connection or configuration mistakes. So the users should note that:
Make sure correct physical connection
Activate IGMP Snooping on whole configuration mode (use ip igmp snooping)
Configure IGMP Snooping at VLAN on whole configuration mode ( use ip igmp
snooping vlan <vlan-id>)
Make sure one VLAN is configured as L2 common checker in same mask, or make
sure configured static mrouter
Use show ip igmp snooping vlan <vid> command check IGMP Snooping
information
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Chapter 39 IPv6 Multicast Protocol
39.1 MLD Snooping
39.1.1 Introduction to MLD Snooping
MLD, the Multicast Listener Discovery Protocol, is used to realize multicasting in the IPv6.
MLD is used by the network equipments such as routers which supports multicast for multicast
listener discovery, also used by listeners looking forward to join certain multicast group
informing the router to receive data packets from certain multicast address, all of which are
done through MLD message exchange. First the router send an MLD Multicast listener Query
message through a multicast address which can address all the listeners (namely ff02::1).
Once there is a listener who wishes to join the multicast address, it will send a MLD Multicast
listener Report back through the multicast address.
MLD Snooping is namely the MLD listening. The switch restricts the multicast traffic from
flooding through MLD Snooping, and forward the multicast traffic to ports associated to
multicast devices only. The switch listens to the MLD messages between multicast routers and
listeners, and maintains the multicast group forwarding list based on the listening result. The
switches forwards multicast packets according to the multicast forwarding list
The switch realizes the MLD Snooping function while supporting MLD v2. This way, the user
can acquire IPv6 multicast with the switch.
39.1.2 MLD Snooping Configuration Task
1. Enable the MLD Snooping function
2. Configure the MLD Snooping
1. Enable the MLD Snooping function
Command Explanation
Global Mode
ipv6 mld snooping
no ipv6 mld snooping
Enable global MLD Snooping, the “no ipv6
mld snooping” command disables the
global MLD snooping.
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2. Configure MLD Snooping
Command Explanation
Global Mode
ipv6 mld snooping vlan <vlan-id>
no ipv6 mld snooping vlan <vlan-id>
Enable MLD Snooping on specific VLAN. The
“no” form of this command disables MLD
Snooping on specific VLAN.
ipv6 mld snooping vlan <vlan-id> limit
{group <g_limit> | source <s_limit>}
no ipv6 mld snooping vlan <vlan-id> limit
Configure the number of the groups in which
the MLD Snooping can join, and the
maximum number of sources in each group.
The “no” form of this command restores to
the default.
ipv6 mld snooping vlan <vlan-id>
l2-general-querier
no ipv6 mld snooping vlan <vlan-id>
l2-general-querier
Set the VLAN level 2 general querier, which
is recommended on each segment. The “no”
form of this command cancels the level 2
general querier configuration.
ipv6 mld snooping vlan <vlan-id>
mrouter-port interface <interface –name>
no ipv6 mld snooping vlan <vlan-id>
mrouter-port interface <interface –name>
Configure the static mrouter port in specific
vlan. The “no” form of this command cancels
the mrouter port configuration.
ipv6 mld snooping vlan <vlan-id>
mrouter-port learnpim6
no ipv6 mld snooping vlan <vlan-id>
mrouter-port learnpim6
Enable the function that the specified VLAN
learns mrouter-port (according to pimv6
packets), the no command will disable the
function.
ipv6 mld snooping vlan <vlan-id> mrpt
<value>
no ipv6 mld snooping vlan <vlan-id> mrpt
Configure the keep-alive time of the mrouter
port. The “no” form of this command restores
to the default.
ipv6 mld snooping vlan <vlan-id>
query-interval <value>
no ipv6 mld snooping vlan <vlan-id>
query-interval
Configure the query interval. The “no” form of
this command restores to the default.
ipv6 mld snooping vlan <vlan-id>
immediate-leave
no ipv6 mld snooping vlan <vlan-id>
immediate-leave
Configure immediate leave multicast group
function for the MLD Snooping of specific
VLAN. The “no” form of this command
cancels the immediate leave configuration.
ipv6 mld snooping vlan <vlan-id>
query-mrsp <value>
no ipv6 mld snooping vlan <vlan-id>
Configure the query maximum response
period. The “no” form of this command
restores to the default.
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query-mrsp
ipv6 mld snooping vlan <vlan-id>
query-robustness <value>
no ipv6 mld snooping vlan <vlan-id>
query-robustness
Configure the query robustness, the “no”
form of this command restores to the default.
ipv6 mld snooping vlan <vlan-id>
suppression-query-time <value>
no ipv6 mld snooping vlan <vlan-id>
suppression-query-time
Configure the suppression query time. The
“no” form of this command restores to the
default
Ipv6 mld snooping vlan <vlan-id>
static-group <X:X::X:X> [source
<X:X::X:X>] interface [ethernet |
port-channel] <IFNAME>
no ipv6 mld snooping vlan <vlan-id>
static-group <X:X::X:X> [source
<X:X::X:X>] interface [ethernet |
port-channel] <IFNAME>
Configure static-group on specified port of
the VLAN. The no form of the command
cancels this configuration.
39.1.3 MLD Snooping Examples
Scenario 1: MLD Snooping Function
Multicast Router
Mrouter Port
MLD Snooping
Switch
Group1 Group1 Group1 Group2
Figure 39-1: Open the switch MLD Snooping Function figure
As shown above, the vlan 100 configured on the switch consists of ports 1, 2, 6, 10 and 12.
Four hosts are respectively connected to 2, 6, 10 and 12 while the multicast router on port 1.
39-43
Suppose we need MLD Snooping on VLAN 100, however by default, the global MLD Snooping
as well as the MLD Snooping on each VLAN are, therefore first we have to enable the global
MLD Snooping at the same time enable the MLD Snooping on VLAN 100, furthermore we
need to set the port 1 of VLAN 100 as a mrouter port.
Configuration procedure is as follows.
Switch#config
Switch(config)#ipv6 mld snooping
Switch(config)#ipv6 mld snooping vlan 100
Switch(config)#ipv6 mld snooping vlan 100 mrouter-port interface ethernet 1/1
Multicast configuration:
Assume there are two multicast servers: the Multicast Server 1 and the Multicast Server 2,
amongst program 1 and 2 are supplied on the Multicast Server 1 while program 3 on the
Multicast server 2, using group addresses respectively the Group 1, Group 2 and Group 3.
Concurrently multicast application is operating on the four hosts. Two hosts connected to port
2, 6 are playing program 1 while the host connected to port 10 playing program 2, and the one
to port 12 playing program 3.
MLD Snooping interception results:
The multicast table on vlan 100 shows: port 1, 2, 6 are in （Multicasting Server 1, Group1）,
port1, 10 are in (Multicasting Server 1,Group2), and port1, 121, 12 are in (Multicasting Server
2, Group3）
All the four hosts successfully receive programs they are interested in. port2, 6 receives no
traffic from program2 and 3; port10 receives no traffic from program 1 and 3, and port12
receives no traffic from program1 and 2.
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Scenario 2: MLD L2-general-querier
Switch B
Switch A
Figure 39-2: Switch as MLD Querier Function figure
Configuration of switch B is the same as the switches in case 1, and here the switch 1 replaces
the Multicast Router in case 1. Assume the vlan 60 configured on it contains port 1, 2, 10 and
12, amongst port 1 is connected to multicast server, port 2 to switch2. To send Query
periodically, global MLD Snooping has to be enabled while executing the mld snooping vlan 60
l2-general-querier, setting the vlan 60 to a Level 2 General Querier.
Configuration procedure is as follows:
SwitchA#config
SwitchA(config)#ipv6 mld snooping
SwitchA(config)#ipv6 mld snooping vlan 60
SwitchA(config)#ipv6 mld snooping vlan 60 l2-general-querier
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SwitchB#config
SwitchB(config)#ipv6 mld snooping
SwitchB(config)#ipv6 mld snooping vlan 100
SwitchB(config)#ipv6 mld snooping vlan 100 mrouter interface ethernet 1/1
Multicast configuration:
Same as scenario 1
MLD Snooping interception results:
Same as scenario 1
39.1.4 MLD Snooping Troubleshooting
In configuring and using MLD Snooping, the MLD Snooping server may fail to run properly due
to physical connection failure, wrong configuration, etc. The user should ensure the following:
Ensure the physical connection is correct
Ensure the MLD Snooping is enabled under global mode (using ipv6 mld snooping)
Ensure the MLD Snooping is configured on the vlan under global mode (using ipv6
mld snooping vlan <vlan-id>）
Ensure there is a vlan configured as a L2 general querier, or there is a static mrouter
configured in a segment,
Use command to check if the MLD snooping information is correct
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Chapter 40 Multicast VLAN
40.1 Introductions to Multicast VLAN
Based on current multicast order method, when orders from users in different VLAN, each
VLAN will copy a multicast traffic in this VLAN, which is a great waste of the bandwidth. By
configuration of the multicast VLAN, we add the switch port to the multicast VLAN, with the
IGMP Snooping/MLD Snooping functions enabled, users from different VLAN will share the
same multicast VLAN. The multicast traffic only exists within a multicast VLAN, so the
bandwidth is saved. As the multicast VLAN is absolutely separated from the user VLAN,
security and bandwidth concerns can be met at the same time, after the multicast VLAN is
configured, the multicast traffic will be continuously sent to the users.
40.2 Multicast VLAN Configuration Task List
1. Enable the multicast VLAN function
2. Configure the IGMP Snooping
3. Configure the MLD Snooping
1. Enable the multicast VLAN function
Command Explanation
VLAN Mode
multicast-vlan
no multicast-vlan
Configure a VLAN and enable the multicast
VLAN on it. The “no multicast-vlan”
command disables the multicast function on
the VLAN.
multicast-vlan association <vlan-list>
no multicast-vlan association <vlan-list>
Associate a multicast VLAN with several
VLANs. The no form of this command deletes
the related VLANs associated with the
multicast VLAN.
multicast-vlan association interface
(ethernet | port-channel|) IFNAME
no multicast-vlan association interface
(ethernet | port-channel|) IFNAME
Associate the specified port with the multicast
VLAN, so the associated ports are able to
receive the multicast flow. The no command
cancels the association between the ports
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and the multicast VLAN.
2. Configure the IGMP Snooping
Command Explanation
Global Mode
ip igmp snooping vlan <vlan-id>
no ip igmp snooping vlan <vlan-id>
Enable the IGMP Snooping function on the
multicast VLAN. The no form of this command
disables the IGMP Snooping on the multicast
VLAN.
ip igmp snooping
no ip igmp snooping
Enable the IGMP Snooping function. The no
form of this command disables the IGMP
snooping function.
3. Configure the MLD Snooping
ipv6 mld snooping vlan <vlan-id>
no ipv6 mld snooping vlan <vlan-id>
Enable MLD Snooping on multicast VLAN;
the no form of this command disables MLD
Snooping on multicast VLAN.
ipv6 mld snooping
no ipv6 mld snooping
Enable the MLD Snooping function. The no
form of this command disables the MLD
snooping function.
40.3 Multicast VLAN Examples
Figure 40-1: Function configuration of the Multicast VLAN
40-48
As shown in the figure, the multicast server is connected to the layer 3 switch switchA through
port 1/1 which belongs to the VLAN10 of the switch. The layer 3 switch switchA is connected
with layer 2 switches through the port1/10, which configured as trunk port. On the switchB the
VLAN100 is configured set to contain port1/15, and VLAN101 to contain port1/20. PC1 and
PC2 are respectively connected to port 1/15 and1/20. The switchB is connected with the
switchA through port1/10, which configured as trunk port. VLAN 20 is a multicast VLAN. By
configuring multicast vlan, the PC1 and PC2 will receives the multicast data from the multicast
VLAN.
The following configuration based on the IP address of the switch has been configured and all
the equipment are connected correctly.
Configuration procedure
SwitchA#config
SwitchA(config)#vlan 10
SwitchA(config-vlan10)#switchport access ethernet 1/1
SwitchA(config-vlan10)exit
SwitchA(config)#interface vlan 10
Switch(Config-if-Vlan10)#ip pim dense-mode
Switch(Config-if-Vlan10)#exit
SwitchA(config)#vlan 20
SwitchA(config-vlan20)#exit
SwitchA(config)#interface vlan 20
SwitchA(Config-if-Vlan20)#ip pim dense-mode
SwitchA(Config-if-Vlan20)#exit
SwitchA(config)#ip pim multicast
SwitchA(config)# interface ethernet1/10
SwitchA(Config-If-Ethernet1/10)switchport mode trunk
SwitchB#config
SwitchB(config)#vlan 100
SwitchB(config-vlan100)#Switchport access ethernet 1/15
SwitchB(config-vlan100)exit
SwitchB(config)#vlan 101
SwitchB(config-vlan101)#Switchport access ethernet 1/20
SwitchB(config-vlan101)exit
SwitchB(config)# interface ethernet 1/10
SwitchB(Config-If-Ethernet1/10)#switchport mode trunk
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SwitchB(Config-If-Ethernet1/10)#exit
SwitchB(config)#vlan 20
SwitchB(config-vlan20)#multicast-vlan
SwitchB(config-vlan20)#multicast-vlan association 100,101
SwitchB(config-vlan20)#exit
SwitchB(config)#ip igmp snooping
SwitchB(config)#ip igmp snooping vlan 20
When multicast VLAN supports IPv6 multicast, usage is the same as IPv4, but the difference is
using with MLD Snooping, so an example is not given.
40-50
Chapter 41 ACL Configuration
41.1 Introduction to ACL
ACL (Access Control List) is an IP packet filtering mechanism employed in switches, providing
network traffic control by granting or denying access the switches, effectively safeguarding the
security of networks. The user can lay down a set of rules according to some information
specific to packets, each rule describes the action for a packet with certain information
matched: “permit” or “deny”. The user can apply such rules to the incoming direction of switch
ports, so that data streams of specified ports must comply with the ACL rules assigned.
41.1.1 Access-list
Access-list is a sequential collection of conditions that corresponds to a specific rule. Each rule
consist of filter information and the action when the rule is matched. Information included in a
rule is the effective combination of conditions such as source IP, destination IP, IP protocol
number and TCP port, UDP port. Access-lists can be categorized by the following criteria:
Filter information based criterion: IP access-list (layer 3 or higher information), MAC
access-list (layer 2 information), and MAC-IP access-list (layer 2 or layer 3 or
higher).
Configuration complexity based criterion: standard and extended, the extended
mode allows more specific filtering of information.
Nomenclature based criterion: numbered and named.
Description of an ACL should cover the above three aspects.
41.1.2 Access-group
When a set of access-lists are created, they can be applied to traffic of incoming direction on
all ports. Access-group is the description to the binding of an access-list to the incoming
direction on a specific port. When an access-group is created, all packets from in the incoming
direction through the port will be compared to the access-list rule to decide whether to permit
or deny access. The current firmware only supports ingress ACL configuration.
41.1.3 Access-list Action and Global Default Action
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There are two access-list actions and default actions: “permit” or “deny”. The following rules
apply:
An access-list can consist of several rules. Filtering of packets compares packet
conditions to the rules, from the first rule to the first matched rule; the rest of the
rules will not be processed. Global default action applies only to IP packets in the
incoming direction on the ports.
Global default action applies only when packet flirter is enabled on a port and no
ACL is bound to that port, or no binding ACL matches.
41.2 ACL Configuration Task List
ACL Configuration Task Sequence:
1. Configuring access-list
(1) Configuring a numbered standard IP access-list
(2) Configuring a numbered extended IP access-list
(3) Configuring a standard IP access-list based on nomenclature
a) Create a standard IP access-list based on nomenclature
b) Specify multiple “permit” or “deny” rule entries
c) Exit ACL Configuration Mode
(4) Configuring an extended IP access-list based on nomenclature
a) Create an extensive IP access-list based on nomenclature
b) Specify multiple “permit” or “deny” rule entries
c) Exit ACL Configuration Mode
(5) Configuring a numbered standard MAC access-list
(6) Configuring a numbered extended MAC access-list
(7) Configuring a extended MAC access-list based on nomenclature
a) Create a extensive MAC access-list based on nomenclature
b) Specify multiple “permit” or “deny” rule entries
c) Exit ACL Configuration Mode
(8) Configuring a numbered extended MAC-IP access-list
(9) Configuring a extended MAC-IP access-list based on nomenclature
a) Create a extensive MAC-IP access-list based on nomenclature
b) Specify multiple “permit” or “deny” rule entries
c) Exit MAC-IP Configuration Mode
(10) Configuring a numbered standard IPv6 access-list
(11) Configuring a standard IPv6 access-list based on nomenclature
a) Create a standard IPv6 access-list based on nomenclature
41-52
b) Specify multiple permit or deny rule entries
c) Exit ACL Configuration Mode
2. Configuring the packet filtering function
(1) Enable global packet filtering function
(2) Configure default action
3. Configuring time range function
(1) Create the name of the time range
(2) Configure periodic time range
(3) Configure absolute time range
4. Bind access-list to an incoming direction of the specified port
5. Clear the filtering information of the specified port
1. Configuring access-list
(1) Configuring a numbered standard IP access-list
Command Explanation
Global Mode
access-list <num> {deny | permit} {{<sIpAddr>
<sMask>} | any-source | {host-source <sIpAddr>}}
no access-list <num>
Creates a numbered standard IP
access-list, if the access-list
already exists, then a rule will
add to the current access-list;
the “no access-list
<num>“ command deletes a
numbered standard IP
access-list.
(2) Configuring a numbered extensive IP access-list
Command Explanation
Global Mode
access-list <num> {deny | permit} icmp {{<sIpAddr>
<sMask>} | any-source | {host-source <sIpAddr>}}
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [<icmp-type>
[<icmp-code>]] [precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates a numbered ICMP
extended IP access rule; if the
numbered extended access-list
of specified number does not
exist, then an access-list will be
created using this number.
41-53
access-list <num> {deny | permit} igmp {{<sIpAddr>
<sMask>} | any-source | {host-source <sIpAddr>}}
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [<igmp-type>]
[precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates a numbered IGMP
extended IP access rule; if the
numbered extended access-list
of specified number does not
exist, then an access-list will be
created using this number.
access-list <num> {deny | permit} tcp {{<sIpAddr>
<sMask>} | any-source | {host-source <sIpAddr>}}
[s-port {<sPort> | range <sPortMin> <sPortMax>}]
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [d-port {<dPort> |
range <dPortMin> <dPortMax>}]
[ack+fin+psh+rst+urg+syn] [precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates a numbered TCP
extended IP access rule; if the
numbered extended access-list
of specified number does not
exist, then an access-list will be
created using this number.
access-list <num> {deny | permit} udp {{<sIpAddr>
<sMask>} | any-source | {host-source <sIpAddr>}}
[s-port {<sPort> | range <sPortMin> <sPortMax>}]
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [d-port {<dPort> |
range <dPortMin> <dPortMax>}] [precedence
<prec>] [tos <tos>][time-range<time-range-name>]
Creates a numbered UDP
extended IP access rule; if the
numbered extended access-list
of specified number does not
exist, then an access-list will be
created using this number.
access-list <num> {deny | permit} {eigrp | gre | igrp |
ipinip | ip | ospf | <protocol-num>} {{<sIpAddr>
<sMask>} | any-source | {host-source <sIpAddr>}}
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [precedence <prec>]
[tos <tos>][time-range<time-range-name>]
Creates a numbered IP
extended IP access rule for
other specific IP protocol or all IP
protocols; if the numbered
extended access-list of specified
number does not exist, then an
access-list will be created using
this number.
no access-list <num> Deletes a numbered extensive
IP access-list.
(3) Configuring a standard IP access-list basing on nomenclature
a. Create a name-based standard IP access-list
Command Explanation
Global Mode
41-54
ip access-list standard <name>
no ip access-list standard <name>
Creates a standard IP
access-list based on
nomenclature; the “no ip
access-list standard
<name>“ command deletes
the name-based standard IP
access-list.
b. Specify multiple “permit” or “deny” rules
Command Explanation
Standard IP ACL Mode
[no] {deny | permit} {{<sIpAddr> <sMask>} |
any-source | {host-source <sIpAddr>}}
Creates a standard
name-based IP access rule;
the “no” form command
deletes the name-based
standard IP access rule.
c. Exit name-based standard IP ACL configuration mode
Command Explanation
Standard IP ACL Mode
exit Exits name-based standard IP
ACL configuration mode.
(4) Configuring an name-based extended IP access-list
a. Create an extended IP access-list basing on nomenclature
Command Explanation
Global Mode
ip access-list extended <name>
no ip access-list extended <name>
Creates an extended IP
access-list basing on
nomenclature; the “no ip
access-list extended
<name> “ command deletes
the name-based extended IP
access-list.
41-55
b. Specify multiple “permit” or “deny” rules
Command Explanation
Extended IP ACL Mode
[no] {deny | permit} icmp {{<sIpAddr> <sMask>} |
any-source | {host-source <sIpAddr>}} {{<dIpAddr>
<dMask>} | any-destination | {host-destination
<dIpAddr>}} [<icmp-type> [<icmp-code>]]
[precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates an extended
name-based ICMP IP access
rule; the no form command
deletes this name-based
extended IP access rule.
[no] {deny | permit} igmp {{<sIpAddr> <sMask>} |
any-source | {host-source <sIpAddr>}} {{<dIpAddr>
<dMask>} | any-destination | {host-destination
<dIpAddr>}} [<igmp-type>] [precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates an extended
name-based IGMP IP access
rule; the no form command
deletes this name-based
extended IP access rule.
[no] {deny | permit} tcp {{<sIpAddr> <sMask>} |
any-source | {host-source <sIpAddr>}} [s-port
{<sPort> | range <sPortMin> <sPortMax>}]
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [d-port {<dPort> |
range <dPortMin> <dPortMax>}]
[ack+fin+psh+rst+urg+syn] [precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates an extended
name-based TCP IP access
rule; the no form command
deletes this name-based
extended IP access rule.
[no] {deny | permit} udp {{<sIpAddr> <sMask>} |
any-source | {host-source <sIpAddr>}} [s-port
{<sPort> | range <sPortMin> <sPortMax>}]
{{<dIpAddr> <dMask>} | any-destination |
{host-destination <dIpAddr>}} [d-port {<dPort> |
range <dPortMin> <dPortMax>}] [precedence
<prec>] [tos <tos>][time-range<time-range-name>]
Creates an extended
name-based UDP IP access
rule; the no form command
deletes this name-based
extended IP access rule.
[no] {deny | permit} {eigrp | gre | igrp | ipinip | ip |
ospf | <protocol-num>} {{<sIpAddr> <sMask>} |
any-source | {host-source <sIpAddr>}} {{<dIpAddr>
<dMask>} | any-destination | {host-destination
<dIpAddr>}} [precedence <prec>] [tos
<tos>][time-range<time-range-name>]
Creates an extended
name-based IP access rule
for other IP protocols; the no
form command deletes this
name-based extended IP
access rule.
41-56
c. Exit extended IP ACL configuration mode
Command Explanation
Extended IP ACL Mode
exit Exits extended name-based
IP ACL configuration mode.
(5) Configuring a numbered standard MAC access-list
Command Explanation
Global Mode
access-list<num>{deny|permit}{any-source-mac|{ho
st-source-mac<host_smac>}|{<smac><smac-mask>}
}
no access-list <num>
Creates a numbered standard
MAC access-list, if the
access-list already exists,
then a rule will add to the
current access-list; the “no
access-list
<num>“ command deletes a
numbered standard MAC
access-list.
(6) Creates a numbered MAC extended access-list
Command Explanation
Global Mode
access-list<num> {deny|permit} {any-source-mac|
{host-source-mac<host_smac>}|{<smac><smac-ma
sk>}}{any-destination-mac|{host-destination-mac<h
ost_dmac>}|{<dmac><dmac-mask>}}[untagged-eth2
| tagged-eth2 | untagged-802-3 | tagged-802-3]
no access-list <num>
Creates a numbered MAC
extended access-list, if the
access-list already exists,
then a rule will add to the
current access-list; the “no
access-list
<num>“ command deletes a
numbered MAC extended
access-list.
(7) Configuring a extended MAC access-list based on nomenclature
a. Create an extensive MAC access-list based on nomenclature
41-57
Command Explanation
Global Mode
mac-access-list extended <name>
no mac-access-list extended <name>
Creates an extended
name-based MAC access rule
for other IP protocols; the no
form command deletes this
name-based extended MAC
access rule.
b. Specify multiple “permit” or “deny” rule entries
Command Explanation
Extended name-based MAC access rule Mode
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac
<host_dmac>} |{<dmac> <dmac-mask>}} [cos
<cos-val> [<cos-bitmask>] [vlanId <vid-value>
[<vid-mask>][ethertype<protocol>[<protocol-mask>]
]]]
Creates an extended
name-based MAC access rule
matching MAC frame; the no
form command deletes this
name-based extended MAC
access rule.
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}{any-destin
ation-mac|{host-destination-mac<host_dmac>}|{<d
mac><dmac-mask>}}[untagged-eth2 [ethertype
<protocol> [protocol-mask]]]
Creates an extended
name-based MAC access rule
matching untagged ethernet 2
frame; the no form command
deletes this name-based
extended MAC access rule.
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}
[untagged-802-3]
Creates an name-based
extended MAC access rule
matching 802.3 frame; the no
form command deletes this
name-based extended MAC
access rule.
41-58
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}{any-destin
ation-mac|{host-destination-mac<host_dmac>}|{<d
mac><dmac-mask>}}[tagged-eth2 [cos <cos-val>
[<cos-bitmask>]] [vlanId <vid-value> [<vid-mask>]]
[ethertype<protocol> [<protocol-mask>]]]
Creates an name-based
extended MAC access rule
matching tagged ethernet 2
frame; the no form command
deletes this name-based
extended MAC access rule.
[no]{deny|permit}{any-source-mac|{host-source-ma
c <host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac<host_d
mac>}|{<dmac><dmac-mask>}} [tagged-802-3 [cos
<cos-val> [<cos-bitmask>]] [vlanId <vid-value>
[<vid-mask>]]]
Creates an name-based
extended MAC access rule
matching tagged 802.3 frame;
the no form command deletes
this name-based extended
MAC access rule.
c. Exit ACL Configuration Mode
Command Explanation
Extended name-based MAC access configure Mode
exit
Quit the extended
name-based MAC access
configure mode.
(8) Configuring a numbered extended MAC-IP access-list
Command Explanation
Global Mode
access-list<num>{deny|permit} {any-source-mac|
{host-source-mac <host_smac>} | {<smac>
<smac-mask>}} {any-destination-mac |
{host-destination-mac <host_dmac>} |
{<dmac><dmac-mask>}} icmp {{<source>
<source-wildcard>} |any-source| {host-source
<source-host-ip>}} {{<destination>
<destination-wildcard>} | any-destination |
{host-destination <destination-host-ip>}}
[<icmp-type> [<icmp-code>]] [precedence
<precedence>] [tos <tos>] [time-range
<time-range-name>]
Creates a numbered
mac-icmp extended mac-ip
access rule; if the numbered
extended access-list of
specified number does not
exist, then an access-list will
be created using this number.
access-list<num>{deny|permit}{any-source-mac| Creates a numbered
41-59
{host-source-mac<host_smac>}|{<smac><smac-ma
sk>}} {any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}igmp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}}
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination<destination-host-ip>}}
[<igmp-type>] [precedence <precedence>] [tos
<tos>][time-range<time-range-name>]
mac-igmp extended mac-ip
access rule; if the numbered
extended access-list of
specified number does not
exist, then an access-list will
be created using this number.
access-list<num>{deny|permit}{any-source-mac|
{host-source-mac<host_smac>}|{<smac><smac-ma
sk>}}{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}tcp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}} [s-port {<port1> |
range <sPortMin> <sPortMax>}]
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination <destination-host-ip>}} [d-port
{<port3> | range <dPortMin> <dPortMax>}]
[ack+fin+psh+rst+urg+syn] [precedence
<precedence>] [tos
<tos>][time-range<time-range-name>]
Creates a numbered mac-ip
extended mac-tcp access
rule; if the numbered
extended access-list of
specified number does not
exist, then an access-list will
be created using this number.
access-list<num>{deny|permit}{any-source-mac|
{host-source-mac<host_smac>}|{<smac><smac-ma
sk>}}{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}udp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}} [s-port {<port1> |
range <sPortMin> <sPortMax>}]
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination<destination-host-ip>}} [d-port
{<port3> | range <dPortMin> <dPortMax>}]
[precedence <precedence>] [tos
<tos>][time-range<time-range-name>]
Creates a numbered mac-udp
extended mac-ip access rule;
if the numbered extended
access-list of specified
number does not exist, then
an access-list will be created
using this number.
access-list<num>{deny|permit}{any-source-mac|
{host-source-mac<host_smac>}|{<smac><smac-ma
sk>}} {any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}
Creates a numbered
extended mac-ip access rule
for other specific mac-ip
protocols or all mac-ip
41-60
{eigrp|gre|igrp|ip|ipinip|ospf|{<protocol-num>}}
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}}
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination<destination-host-ip>}}
[precedence <precedence>] [tos
<tos>][time-range<time-range-name>]
protocols; if the numbered
extended access-list of
specified number does not
exist, then an access-list will
be created using this number.
no access-list <num>
Deletes this numbered
extended MAC-IP access
rule.
(9) Configuring a extended MAC-IP access-list based on nomenclature
a. Create an extensive MAC-IP access-list based on nomenclature
Command Explanation
Global Mode
mac-ip-access-list extended <name>
no mac-ip-access-list extended <name>
Creates an extended
name-based MAC-IP access
rule; the no form command
deletes this name-based
extended MAC-IP access
rule.
b. Specify multiple “permit” or “deny” rule entries
Command Explanation
Extended name-based MAC-IP access Mode
[no]{deny|permit}
{any-source-mac|{host-source-mac
<host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}icmp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}}
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination <destination-host-ip>}}
[<icmp-type> [<icmp-code>]] [precedence
<precedence>][tos<tos>][time-range<time-range-na
Creates an extended
name-based MAC-ICMP
access rule; the no form
command deletes this
name-based extended
MAC-ICMP access rule.
41-61
me>]
[no]{deny|permit}{any-source-mac|{host-source-ma
c <host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}igmp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}}
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination <destination-host-ip>}}
[<igmp-type>] [precedence <precedence>] [tos
<tos>][time-range<time-range-name>]
Creates an extended
name-based MAC-IGMP
access rule; the no form
command deletes this
name-based extended
MAC-IGMP access rule.
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}tcp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}} [s-port {<port1> |
range <sPortMin> <sPortMax>}]
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination <destination-host-ip>}} [d-port
{<port3> | range <dPortMin> <dPortMax>}]
[ack+fin+psh+rst+urg+syn]
[precedence<precedence>][tos<tos>][time-range<ti
me-range-name>]
Creates an extended
name-based MAC-TCP
access rule; the no form
command deletes this
name-based extended
MAC-TCP access rule.
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}
{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}udp
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}} [s-port {<port1> |
range <sPortMin> <sPortMax>}]
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination <destination-host-ip>}}
[d-port {<port3> | range <dPortMin> <dPortMax>}]
[precedence <precedence>] [tos
<tos>][time-range<time-range-name>]
Creates an extended
name-based MAC-UDP
access rule; the no form
command deletes this
name-based extended
MAC-UDP access rule.
[no]{deny|permit}{any-source-mac|{host-source-ma
c<host_smac>}|{<smac><smac-mask>}}
Creates an extended
name-based access rule for
41-62
{any-destination-mac|{host-destination-mac
<host_dmac>}|{<dmac><dmac-mask>}}
{eigrp|gre|igrp|ip|ipinip|ospf|{<protocol-num>}}
{{<source><source-wildcard>}|any-source|
{host-source<source-host-ip>}}
{{<destination><destination-wildcard>}|any-destinati
on| {host-destination<destination-host-ip>}}
[precedence<precedence>][tos<tos>][time-range<ti
me-range-name>]
the other IP protocol; the no
form command deletes this
name-based extended access
rule.
c. Exit MAC-IP Configuration Mode
Command Explanation
Extended name-based MAC-IP access Mode
exit Quit extended name-based
MAC-IP access mode.
（10） Configuring a numbered standard IPv6 access-list
Command Explanation
Global Mode
ipv6 access-list <num> {deny | permit} {{<sIPv6Addr>
<sPrefixlen>} | any-source | {host-source
<sIpv6Addr>}}
no ipv6 access-list <num>
Creates a numbered standard
IPv6 access-list, if the
access-list already exists,
then a rule will add to the
current access-list; the “no
access-list
<num>“ command deletes a
numbered standard IPv6
access-list.
（11）Configuring a standard IPv6 access-list based on nomenclature
a. Create a standard IPv6 access-list based on nomenclature
Command Explanation
Global Mode
ipv6 access-list standard <name>
no ipv6 access-list standard <name>
Creates a standard IP
access-list based on
41-63
nomenclature; the no
command delete the
name-based standard IPv6
access-list.
b. Specify multiple permit or deny rules
Command Explanation
Standard IPv6 ACL Mode
[no] {deny | permit} {{<sIPv6Prefix/sPrefixlen>} |
any-source | {host-source <sIPv6Addr> }}
Creates a standard
name-based IPv6 access
rule; the no form command
deletes the name-based
standard IPv6 access rule.
c. Exit name-based standard IP ACL configuration mode
Command Explanation
Standard IPv6 ACL Mode
exit Exits name-based standard
IPv6 ACL configuration mode.
2. Configuring packet filtering function
(1) Enable global packet filtering function
Command Explanation
Global Mode
firewall enable Enables global packet filtering function.
firewall disable Disables global packet filtering function.
3. Configuring time range function
（1）Create the name of the time range
Command Explanation
Global Mode
time-range <time_range_name> Create a time range named
time_range_name.
41-64
no time-range <time_range_name> Stop the time range function named
time_range_name.
（2）Configure periodic time range
Command Explanation
Time range Mode
absolute-periodic {Monday | Tuesday | Wednesday |
Thursday | Friday | Saturday | Sunday} <start_time>
to {Monday | Tuesday | Wednesday | Thursday |
Friday | Saturday | Sunday} <end_time>
periodic
{{Monday+Tuesday+Wednesday+Thursday+
Friday+Saturday+Sunday} | daily | weekdays |
weekend} <start_time> to <end_time>
Configure the time range for
the request of the week, and
every week will run by the
time range.
[no] absolute-periodic {Monday | Tuesday |
Wednesday | Thursday | Friday | Saturday | Sunday}
<start_time> to {Monday | Tuesday | Wednesday |
Thursday | Friday | Saturday | Sunday} <end_time>
[no] periodic
{{Monday+Tuesday+Wednesday+Thursday+
Friday+Saturday+Sunday} | daily | weekdays |
weekend} <start_time> to <end_time>
Stop the function of the time
range in the week.
（3）Configure absolute time range
Command Explanation
Global Mode
absolute start <start_time> <start_data> [end
<end_time> <end_data>]
Configure absolute time
range.
[no] absolute start <start_time> <start_data> [end
<end_time> <end_data>]
Stop the function of the time
range.
4. Bind access-list to a specific direction of the specified port.
Command Explanation
41-65
Physical Port Mode / VLAN Interface Mode
{ip|ipv6|mac|mac-ip} access-group
<acl-name> {in} [traffic-statistic]
no {ip|ipv6|mac|mac-ip} access-group
<acl-name> {in}
Physical interface mode: Applies an
access-list to the specified direction on
the port; the no command deletes the
access-list bound to the port.
VLAN interface mode: Applies an
access-list to the specified direction on
the port of VLAN; the no command
deletes the access-list bound to the port
of VLAN.When the acl of ipv6 is applied
by this switch, it only supports the
standard acl of ipv6.
5. Clear the filtering information of the specified port
Command Explanation
Admin Mode
clear access-group statistic
[ethernet <interface-name> ]
Clear the filtering information of the specified
port.
41.3 ACL Example
Scenario 1:
The user has the following configuration requirements: port 10 of the switch connects to
10.0.0.0/24 segment; ftp is not desired for the user.
Configuration description:
1． Create a proper ACL
2． Configuring packet filtering function
3． Bind the ACL to the port
The configuration steps are listed below:
Switch(config)#access-list 110 deny tcp 10.0.0.0 0.0.0.255 any-destination d-port 21
Switch(config)#firewall enable
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#ip access-group 110 in
Switch(Config-If-Ethernet1/10)#exit
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Switch(config)#exit
Configuration result:
Switch#show firewall
Firewall status: enable.
Switch#show access-lists
access-list 110(used 1 time(s)) 1 rule(s)
access-list 110 deny tcp 10.0.0.0 0.0.0.255 any-destination d-port 21
Switch#show access-group interface ethernet 1/10
interface name:Ethernet1/10
the ingress acl use in firewall is 110, traffic-statistics Disable.
Scenario 2:
The configuration requirements are stated below: The switch should drop all the 802.3
datagrams with 00-12-11-23-xx-xx as the source MAC address coming from interface 10.
Configuration description:
1． Create the corresponding MAC ACL.
2． Configure datagram filtering.
3． Bind the ACL to the related interface.
The configuration steps are listed below.
Switch(config)#access-list 1100 deny 00-12-11-23-00-00 00-00-00-00-ff-ff
any-destination-mac untagged-802-3
Switch(config)#access-list 1100 deny 00-12-11-23-00-00 00-00-00-00-ff-ff any
tagged-802
Switch(config)#firewall enable
Switch(config)#interface ethernet1/10
Switch(Config-If-Ethernet1/10)#mac access-group 1100 in
Switch(Config-If-Ethernet1/10)#exit
Switch(config)#exit
Configuration result:
Switch#show firewall
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Firewall Status: Enable.
Switch #show access-lists
access-list 1100(used 1 time(s))
access-list 1100 deny 00-12-11-23-00-00 00-00-00-00-ff-ff
any-destination-mac
untagged-802-3
access-list 1100 deny 00-12-11-23-00-00 00-00-00-00-ff-ff
any-destination-mac
Switch #show access-group interface ethernet 1/10
interface name:Ethernet1/10
MAC Ingress access-list used is 1100,traffic-statistics Disable.
Scenario 3:
The configuration requirements are stated below: The MAC address range of the network is
connected to the interface 10 of the switch which is 00-12-11-23-xx-xx, and IP network is
10.0.0.0/24. FTP should be disabled and ping requests from outside network should be
disabled.
Configuration description:
1． Create the corresponding access list.
2． Configure datagram filtering.
3． Bind the ACL to the related interface.
The configuration steps are listed below:
Switch(config)#access-list 3110 deny 00-12-11-23-00-00 00-00-00-00-ff-ff
any-destination-mac tcp 10.0.0.0 0.0.0.255 any-destination d-port 21
Switch(config)#access-list 3110 deny any-source-mac 00-12-11-23-00-00
00-00-00-00-ff-ff icmp any-source 10.0.0.0 0.0.0.255
Switch(config)#firewall enable
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#mac-ip access-group 3110 in
Switch(Config-Ethernet1/10)#exit
Switch(config)#exit
Configuration result:
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Switch#show firewall
Firewall Status: Enable.
Switch#show access-lists
access-list 3110(used 1 time(s))
access-list 3110 deny 00-12-11-23-00-00 00-00-00-00-ff-ff
any-destination-mac
tcp 10.0.0.0 0.0.0.255 any-destination d-port 21
access-list 3110 deny any-source-mac 00-12-11-23-00-00 00-00-00-00-ff-ff icmp
any-source 10.0.0.0 0.0.0.255
Switch #show access-group interface ethernet 1/10
interface name:Ethernet1/10
MAC-IP Ingress access-list used is 3110, traffic-statistics Disable.
Scenario 4:
The configuration requirements are stated below: IPv6 protocol runs on the interface 600 of
the switch. And the IPv6 network address is 2003:1:1:1::0/64. Users in the 2003:1:1:1:66::0/80
subnet should be disabled from accessing the outside network.
Configuration description:
1． Create the corresponding access list.
2． Configure datagram filtering.
3． Bind the ACL to the related interface.
The configuration steps are listed below.
Switch(config)#ipv6 access-list 600 permit 2003:1:1:1:66::0/80 any-destination
Switch(config)#ipv6 access-list 600 deny 2003:1:1:1::0/64 any-destination
Switch(config)#firewall enable
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#ipv6 access-group 600 in
Switch(Config-If-Ethernet1/10)#exit
Switch(config)#exit
Configuration result:
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Switch#show firewall
Firewall Status: Enable.
Switch#show ipv6 access-lists
Ipv6 access-list 600(used 1 time(s))
ipv6 access-list 600 deny 2003:1:1:1::0/64 any-source
ipv6 access-list 600 permit 2003:1:1:1:66::0/80 any-source
Switch #show access-group interface ethernet 1/10
interface name:Ethernet1/10
IPv6 Ingress access-list used is 600, traffic-statistics Disable.
Scenario 5:
The configuration requirements are stated below: The interface 1, 2, 5, 7 belongs to vlan100,
Hosts with 192.168.0.1 as its IP address should be disabled from accessing the listed
interfaces.
Configuration description:
1． Create the corresponding access list.
2． Configure datagram filtering.
3． Bind the ACL to the related interface.
The configuration steps are listed below.
Switch (config)#firewall enable
Switch (config)#vlan 100
Switch (Config-Vlan100)#switchport interface ethernet 1/1;2;5;7
Switch (Config-Vlan100)#exit
Switch (config)#access-list 1 deny host-source 192.168.0.1
Switch (config)#interface ethernet1/1;2;5;7
Switch (config-if-port-range)#ip access-group 1 in
Switch (Config-if-Vlan100)#exit
Configuration result:
Switch (config)#show access-group interface vlan 100
Interface VLAN 100:
Ethernet1/1: IP Ingress access-list used is 1, traffic-statistics Disable.
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Ethernet1/2: IP Ingress access-list used is 1, traffic-statistics Disable.
Ethernet1/5: IP Ingress access-list used is 1, traffic-statistics Disable.
Ethernet1/7: IP Ingress access-list used is 1, traffic-statistics Disable.
41.4 ACL Troubleshooting
Checking for entries in the ACL is done in a top-down order and ends whenever an entry
is matched.
Default rule will be used only if no ACL is bound to the incoming direction of the port, or
no ACL entry is matched.Each ingress port can bind one MAC-IP ACL, one IP ACL, one
MAC ACL, one IPv6 ACL (via the physical interface mode or Vlan interface mode).
When binding four ACL and packet matching several ACL at the same time, the priority
relations are as follows in a top-down order. If the priority is same, then the priority of
configuration at first is higher.
Ingress IPv6 ACL
Ingress MAC-IP ACL
Ingress IP ACL
Ingress MAC ACL
The number of ACLs that can be successfully bound depends on the content of the ACL
bound and the hardware resource limit. Users will be prompted if an ACL cannot be
bound due to hardware resource limitation.
If an access-list contains same filtering information but conflicting action rules, binding to
the port will fail with an error message. For instance, configuring “permit tcp any
any-destination” and “deny tcp any any-destination” at the same time is not permitted.
Viruses such as “worm.blaster” can be blocked by configuring ACL to block specific ICMP
packets or specific TCP or UDP port packet.
If the physical mode of an interface is TRUNK, ACL can only be configured through
physical interface mode.
ACL configured in the physical mode can only be disabled in the physical mode. Those
configured in the VLAN interface configuration mode can only be disabled in the VLAN
interface mode.
When a physical interface is added into or removed from a VLAN (with the trunk
interfaces as exceptions), ACL configured in the corresponding VLAN will be bound or
unbound respectively. If ACL configured in the target VLAN, which is configured in VLAN
interface mode, conflicts with existing ACL configuration on the interface, which is
configured in physical interface mode, the configuration will fail to effect.
When no physical interfaces are configured in the VLAN, the ACL configuration of the
VLAN will be removed. And it can not recover if new interfaces are added to the VLAN.
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When the interface mode is changed from access mode to trunk mode, the ACL
configured in VLAN interface mode which is bound to physical interface will be removed.
And when the interface mode is changed from trunk mode to access mode, ACL
configured in VLAN1 interface mode will be bound to the physical interface. If binding
fails, the changing will fail either.
When removing a VLAN configuration, if there are any ACLs bound to the VLAN, the ACL
will be removed from all the physical interfaces belonging to the VLAN, and it will be
bound to VLAN 1 ACL(if ACL is configured in VLAN1). If VLAN 1 ACL binding fails, the
VLAN removal operation will fail.
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Chapter 42 802.1x Configuration
42.1 Introduction to 802.1x
The 802.1x protocol originates from 802.11 protocol, the wireless LAN protocol of IEEE, which
is designed to provide a solution to doing authentication when users access a wireless LAN.
The LAN defined in IEEE 802 LAN protocol does not provide access authentication, which
means as long as the users can access a LAN controlling device (such as a LAN Switch), they
will be able to get all the devices or resources in the LAN. There was no looming danger in the
environment of LAN in those primary enterprise networks.
However, along with the boom of applications like mobile office and service operating networks,
the service providers should control and configure the access from user. The prevailing
application of WLAN and LAN access in telecommunication networks, in particular, make it
necessary to control ports in order to implement the user-level access control. And as a result,
IEEE LAN/WAN committee defined a standard, which is 802.1x, to do Port-Based Network
Access Control. This standard has been widely used in wireless LAN and ethernet.
“Port-Based Network Access Control” means to authenticate and control the user devices on
the level of ports of LAN access devices. Only when the user devices connected to the ports
pass the authentication, can they access the resources in the LAN, otherwise, the resources in
the LAN won’t be available.
42.1.1 The Authentication Structure of 802.1x
The system using 802.1x has a typical Client/Server structure, which contains three entities
(as illustrated in the next figure): Supplicant system, Authenticator system, and Authentication
server system.
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Figure 42-1: The Authentication Structure of 802.1x
The supplicant system is an entity on one end of the LAN segment, should be
authenticated by the access controlling unit on the other end of the link. A Supplicant
system usually is a user terminal device. Users start 802.1x authentication by starting
supplicant system software. A supplicant system should support EAPOL (Extensible
Authentication Protocol over LAN).
The authenticator system is another entity on one end of the LAN segment to
authenticate the supplicant systems connected. An authenticator system usually is a
network device supporting 802,1x protocol, providing ports to access the LAN for
supplicant systems. The ports provided can either be physical or logical.
The authentication server system is an entity to provide authentication service for
authenticator systems. The authentication server system is used to authenticate and
authorize users, as well as does fee-counting, and usually is a RADIUS (Remote
Authentication Dial-In User Service) server, which can store the relative user information,
including username, password and other parameters such as the VLAN and ports which
the user belongs to.
The three entities above concerns the following basic concepts: PAE of the port, the controlled
ports and the controlled direction.
1. PAE
PAE (Port Access Entity) is the entity to implement the operation of algorithms and protocols.
The PAE of the supplicant system is supposed to respond the authentication request
from the authenticator systems and submit user’s authentication information to the
authenticator system. It can also send authentication request and off-line request to
authenticator.
The PAE of the authenticator system authenticates the supplicant systems needing to
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access the LAN via the authentication server system, and deal with the
authenticated/unauthenticated state of the controlled port according to the result of the
authentication. The authenticated state means the user is allowed to access the network
resources, the unauthenticated state means only the EAPOL messages are allowed to
be received and sent while the user is forbidden to access network resources.
2. controlled/uncontrolled ports
The authenticator system provides ports to access the LAN for the supplicant systems. These
ports can be divided into two kinds of logical ports: controlled ports and uncontrolled ports.
The uncontrolled port is always in bi-directionally connected status, and mainly used to
transmit EAPOL protocol frames, to guarantee that the supplicant systems can always
send or receive authentication messages.
The controlled port is in connected status authenticated to transmit service messages.
When unauthenticated, no message from supplicant systems is allowed to be received.
The controlled and uncontrolled ports are two parts of one port, which means each frame
reaching this port is visible on both the controlled and uncontrolled ports.
3. Controlled direction
In unauthenticated status, controlled ports can be set as unidirectional controlled or
bi-directionally controlled.
When the port is bi-directionally controlled, the sending and receiving of all frames is
forbidden.
When the port is unidirectional controlled, no frames can be received from the supplicant
systems while sending frames to the supplicant systems is allowed.
Notes: At present, this kind of switch only supports unidirectional control.
42.1.2 The Work Mechanism of 802.1x
IEEE 802.1x authentication system uses EAP (Extensible Authentication Protocol) to
implement exchange of authentication information between the supplicant system,
authenticator system and authentication server system.
Figure 42-2: the Work Mechanism of 802.1x
EAP messages adopt EAPOL encapsulation format between the PAE of the supplicant
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system and the PAE of the authenticator system in the environment of LAN.
Between the PAE of the authenticator system and the RADIUS server, there are two
methods to exchange information: one method is that EAP messages adopt EAPOR
(EAP over RADIUS) encapsulation format in RADIUS protocol; the other is that EAP
messages terminate with the PAE of the authenticator system, and adopt the messages
containing RAP (Password Authentication Protocol) or CHAP (Challenge Handshake
Authentication Protocol) attributes to do the authentication interaction with the RADIUS
server.
When the user pass the authentication, the authentication server system will send the
relative information of the user to authenticator system, the PAE of the authenticator
system will decide the authenticated/unauthenticated status of the controlled port
according to the authentication result of the RADIUS server.
42.1.3 The Encapsulation of EAPOL Messages
1. The Format of EAPOL Data Packets
EAPOL is a kind of message encapsulation format defined in 802.1x protocol, and is mainly
used to transmit EAP messages between the supplicant system and the authenticator system
in order to allow the transmission of EAP messages through the LAN. In IEEE 802/Ethernet
LAN environment, the format of EAPOL packet is illustrated in the next figure. The beginning of
the EAPOL packet is the Type/Length domain in MAC frames.
Figure 42-3: the Format of EAPOL Data Packet
PAE Ethernet Type: Represents the type of the protocol whose value is 0x888E.
Protocol Version: Represents the version of the protocol supported by the sender of EAPOL
data packets.
Type: represents the type of the EAPOL data packets, including:
EAP-Packet (whose value is 0x00): the authentication information frame, used to carry
EAP messages. This kind of frame can pass through the authenticator system to transmit
EAP messages between the supplicant system and the authentication server system.
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EAPOL-Start (whose value is 0x01): the frame to start authentication.
EAPOL-Logoff (whose value is 0x02): the frame requesting to quit.
EAPOL-Key (whose value is 0x03): the key information frame.
EAPOL-Encapsulated-ASF-Alert (whose value is 0x04): used to support the Alerting
messages of ASF (Alert Standard Forum). This kind of frame is used to encapsulate the
relative information of network management such as all kinds of alerting information,
terminated by terminal devices.
Length: represents the length of the data, that is, the length of the “Packet Body”, in byte.
There will be no following data domain when its value is 0.
Packet Body: represents the content of the data, which will be in different formats according to
different types.
2. The Format of EAP Data Packets
When the value of Type domain in EAPOL packet is EAP-Packet, the Packet Body is in EAP
format (illustrated in the next figure).
Figure 42-4: the Format of EAP Data Packets
Code: specifies the type of the EAP packet. There are four of them in total: Request
（1）,Response（2）,Success（3）,Failure（4）.
There is no Data domain in the packets of which the type is Success or Failure, and the
value of the Length domains in such packets is 4.
The format of Data domains in the packets of which the type is Request and Response is
illustrated in the next figure. Type is the authentication type of EAP, the content of Type
data depends on the type. For example, when the value of the type is 1, it means Identity,
and is used to query the identity of the other side. When the type is 4, it means
MD5-Challenge, like PPP CHAP protocol, contains query messages.
Figure 42-5: the Format of Data Domain in Request and Response Packets
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Identifier: to assist matching the Request and Response messages.
Length: the length of the EAP packet, covering the domains of Code, Identifier, Length and
Data, in byte.
Data: the content of the EAP packet, depending on the Code type.
42.1.4 The Encapsulation of EAP Attributes
RADIUS adds two attribute to support EAP authentication: EAP-Message and
Message-Authenticator. Please refer to the Introduction of RADIUS protocol in
“AAA-RADIUS-HWTACACS operation” to check the format of RADIUS messages.
1. EAP-Message
As illustrated in the next figure, this attribute is used to encapsulate EAP packet, the type code
is 79, String domain should be no longer than 253 bytes. If the data length in an EAP packet is
larger than 253 bytes, the packet can be divided into fragments, which then will be
encapsulated in several EAP-Messages attributes in their original order.
Figure 42-6: the Encapsulation of EAP-Message Attribute
2. Message-Authenticator
As illustrated in the next figure, this attribute is used in the process of using authentication
methods like EAP and CHAP to prevent the access request packets from being eavesdropped.
Message-Authenticator should be included in the packets containing the EAP-Message
attribute, or the packet will be dropped as an invalid one.
Figure 42-7: Message-Authenticator Attribute
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42.1.5 The Authentication Methods of 802.1x
The authentication can either be started by supplicant system initiatively or by devices. When
the device detects unauthenticated users to access the network, it will send supplicant system
EAP-Request/Identity messages to start authentication. On the other hand, the supplicant
system can send EAPOL-Start message to the device via supplicant software.
802.1 x systems supports EAP relay method and EAP termination method to implement
authentication with the remote RADIUS server. The following is the description of the process
of these two authentication methods, both started by the supplicant system.
42.1.5.1 EAP Relay Mode
EAP relay is specified in IEEE 802.1x standard to carry EAP in other high-level protocols, such
as EAP over RADIUS, making sure that extended authentication protocol messages can reach
the authentication server through complicated networks. In general, EAP relay requires the
RADIUS server to support EAP attributes: EAP-Message and Message-Authenticator.
EAP is a widely-used authentication frame to transmit the actual authentication protocol rather
than a special authentication mechanism. EAP provides some common function and allows
the authentication mechanisms expected in the negotiation, which are called EAP Method.
The advantage of EAP lies in that EAP mechanism working as a base needs no adjustment
when a new authentication protocol appears. The following figure illustrates the protocol stack
of EAP authentication method.
Figure 42-8: the Protocol Stack of EAP Authentication Method
By now, there are more than 50 EAP authentication methods that have been developed. The
differences among which are those in the authentication mechanism and the management of
keys. The 4 most common EAP authentication methods are listed as follows:
EAP-MD5
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EAP-TLS（Transport Layer Security）
EAP-TTLS（Tunneled Transport Layer Security）
PEAP（Protected Extensible Authentication Protocol）
They will be described in details in the following part.
Attention:
The switch, as the access controlling unit of Pass-through, will not check the content of a
particular EAP method, so can support all the EAP methods above and all the EAP
authentication methods that may be extended in the future.
In EAP relay, if any authentication method in EAP-MD5, EAP-TLS, EAP-TTLS and PEAP
is adopted, the authentication methods of the supplicant system and the RADIUS server
should be the same.
1. EAP-MD5 Authentication Method
EAP-MD5 is an IETF open standard which providing the least security, since MD5 Hash
function is vulnerable to dictionary attacks.
The following figure illustrated the basic operation flow of the EAP-MD5 authentication
method.
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Figure 42-9: the Authentication Flow of 802.1x EAP-MD5
2. EAP-TLS Authentication Method
EAP-TLS is brought up by Microsoft based on EAP and TLS protocols. It uses PKI to protect
the id authentication between the supplicant system and the RADIUS server and the
dynamically generated session keys, requiring both the supplicant system and the Radius
authentication server to possess digital certificate to implement bidirectional authentication. It
is the earliest EAP authentication method used in wireless LAN. Since every user should have
a digital certificate, this method is rarely used practically considering the difficult maintenance.
However it is still one of the safest EAP standards, and enjoys prevailing supports from the
vendors of wireless LAN hardware and software.
The following figure illustrates the basic operation flow of the EAP-TLS authentication method.
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Figure 42-10: the Authentication Flow of 802.1x EAP-TLS
3. EAP-TTLS Authentication Method
EAP-TTLS is a product of the cooperation of Funk Software and Certicom. It can provide an
authentication as strong as that provided by EAP-TLS, but without requiring users to have their
own digital certificate. The only request is that the Radius server should have a digital
certificate. The authentication of users’ identity is implemented with passwords transmitted in a
safely encrypted tunnel established via the certificate of the authentication server. Any kind of
authentication request including EAP, PAP and MS-CHAPV2 can be transmitted within TTLS
tunnels.
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4. PEAP Authentication Method
EAP-PEAP is brought up by Cisco, Microsoft and RAS Security as a recommended open
standard. It has long been utilized in products and provides very good security. Its design of
protocol and security is similar to that of EAP-TTLS, using a server’s PKI certificate to
establish a safe TLS tunnel in order to protect user authentication.
The following figure illustrates the basic operation flow of PEAP authentication method.
Figure 42-11: the Authentication Flow of 802.1x PEAP
42.1.5.2 EAP Termination Mode
In this mode, EAP messages will be terminated in the access control unit and mapped into
RADIUS messages, which is used to implement the authentication, authorization and
fee-counting. The basic operation flow is illustrated in the next figure.
In EAP termination mode, the access control unit and the RADIUS server can use PAP or
CHAP authentication method. The following figure will demonstrate the basic operation flow
using CHAP authentication method.
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Figure 42-12: the Authentication Flow of 802.1x EAP Termination Mode
42.1.6 The Extension and Optimization of 802.1x
Besides supporting the port-based access authentication method specified by the protocol,
devices also extend and optimize it when implementing the EAP relay mode and EAP
termination mode of 802.1x.
Supports some applications in the case of which one physical port can have more than
one users
There are three access control methods (the methods to authenticate users): port-based,
MAC-based and user-based (IP address+ MAC address+ port).
When the port-based method is used, as long as the first user of this port passes the
authentication, all the other users can access the network resources without being
authenticated. However, once the first user is offline, the network won’t be available
to all the other users.
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When the MAC-based method is used, all the users accessing a port should be
authenticated separately, only those pass the authentication can access the network,
while the others can not. When one user becomes offline, the other users will not be
affected.
When the user-based (IP address+ MAC address+ port) method is used, all users
can access limited resources before being authenticated. There are two kinds of
control in this method: standard control and advanced control. The user-based
standard control will not restrict the access to limited resources, which means all
users of this port can access limited resources before being authenticated. The
user-based advanced control will restrict the access to limited resources, only some
particular users of the port can access limited resources before being authenticated.
Once those users pass the authentication, they can access all resources.
Attention: When using private supplicant systems, user-based advanced control is
recommended to effectively prevent ARP cheat. The maximum number of the authenticated
users can be 4000, but less than 2000 will be preferred.
42.1.7 The Features of VLAN Allocation
1. Auto VLAN
Auto VLAN feature enables RADIUS server to change the VLAN to which the access port
belongs, based on the user information and the user access device information. When an
802.1x user passes authentication on the server, the RADIUS server will send the
authorization information to the device, if the RADIUS server has enabled the VLAN-assigning
function, then the following attributes should be included in the Access-Accept messages:
Tunnel-Type = VLAN (13)
Tunnel-Medium-Type = 802 (6)
Tunnel-Private-Group-ID = VLANID
The VLANID here means the VID of VLAN, ranging from 1 to 4094. For example,
Tunnel-Private-Group-ID = 30 means VLAN 30.
When the switch receives the assigned Auto VLAN information, the current Access port will
leave the VLAN set by the user and join Auto VLAN. Auto VLAN won’t change or affect the
port’s configuration. But the priority of Auto VLAN is higher than that of the user-set VLAN, that
is Auto VLAN is the one takes effect when the authentication is finished, while the user-set
VLAN do not work until the user become offline.
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Notes: At present, Auto VLAN can only be used in the port-based access control mode, and on
the ports whose link type is Access.
2. Guest VLAN
Guest VLAN feature is used to allow the unauthenticated user to access some specified
resources. The user authentication port belongs to a default VLAN (Guest VLAN) before
passing the 802.1x authentication, with the right to access the resources within this VLAN
without authentication. But the resources in other networks are beyond reach. Once
authenticated, the port will leave Guest VLAN, and the user can access the resources of other
networks.
In Guest VLAN, users can get 802.1x supplicant system software, update supplicant system or
update some other applications (such as anti-virus software, the patches of operating system).
The access device will add the port into Guest VLAN if there is no supplicant getting
authenticated successfully in a certain stretch of time because of lacking exclusive
authentication supplicant system or the version of the supplicant system being too low.
Once the 802.1x feature is enabled and the Guest VLAN is configured properly, a port will be
added into Guest VLAN, just like Auto VLAN, if there is no response message from the
supplicant system after the device sends more authentication-triggering messages than the
upper limit (EAP-Request/Identity) from the port.
The authentication server assigns an Auto VLAN, and then the port leaves Guest VLAN
and joins the assigned Auto VLAN. When the user becomes offline, the port will be
allocated to the specified Guest VLAN again.
The authentication server assigns an Auto VLAN, and then the port leaves Guest VLAN
and joins the specified VLAN. When the user becomes offline, the port will be allocated to
the specified Guest VLAN again.
42.2 802.1x Configuration Task List
802.1x Configuration Task List:
1. Enable IEEE 802.1x function
2. Access management unit property configuration
1) Configure port authentication status
2) Configure access management method for the port: MAC-based or port-based
3) Configure expanded 802.1x function
4) Configure IPv6 passthrough function of the port
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3. User access devices related property configuration (optional)
1. Enable 802.1x function
Command Explanation
Global Mode
dot1x enable
no dot1x enable
Enables the 802.1x function in the switch and ports; the no
command disables the 802.1x function.
dot1x privateclient enable
no dot1x privateclient enable
Enables the switch force client software using private
802.1x authentication packet format. The no command will
disable this function.
dot1x user free-resource
<prefix> <mask>
no dot1x user free-resource
Sets free access network resource for unauthorized dot1x
user. The no command close the resource.
dot1x unicast enable
no dot1x unicast enable
Enable the 802.1x unicast passthrough function of switch;
the no operation of this command will disable this function.
2. Access management unit property configuration
1) Configure port authentication status
Command Explanation
Port Mode
dot1x port-control
{auto|force-authorized|force-
unauthorized }
no dot1x port-control
Sets the 802.1x authentication mode; the no command
restores the default setting.
2) Configure port access management method
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dot1x guest-vlan <vlanID>
no dot1x guest-vlan
Set the guest vlan of the specified port; the
no command is used to delete the guest
vlan.
dot1x portbased mode single-mode
no dot1x portbased mode single-mode
Set the single-mode based on portbase
authentication mode; the no command
disables this function.
3) Configure expanded 802.1x function
Command Explanation
Global Mode
dot1x macfilter enable
no dot1x macfilter enable
Enables the 802.1x address filter function in the switch; the
no command disables the 802.1x address filter function.
dot1x macbased
port-down-flush
no dot1x macbased
port-down-flush
Enables this command, when the dot1x certification
according to mac is down, delete the user who passed the
certification of the port; The no command does not make
the down operation.
Command Explanation
Port Mode
dot1x port-method {macbased |
portbased | userbased {standard |
advanced}}
no dot1x port-method
Sets the port access management method;
the no command restores MAC-based
access management.
dot1x max-user macbased <number>
no dot1x max-user macbased
Sets the maximum number of access users
for the specified port; the no command
restores the default setting of allowing 1
user.
dot1x max-user userbased <number>
no dot1x max-user userbased
Set the upper limit of the number of users
allowed accessing the specified port, only
used when the access control mode of the
port is userbased; the no command is used
to reset the limit to 10 by default.
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dot1x accept-mac
<mac-address> [interface
<interface-name> ]
no dot1x accept-mac
<mac-address> [interface
<interface-name> ]
Adds 802.1x address filter table entry, the no command
deletes 802.1x filter address table entries.
dot1x eapor enable
no dot1x eapor enable
Enables the EAP relay authentication function in the
switch; the no command sets EAP local end
authentication.
4) Configure IPv6 passthrough function of the port
Command Explanation
Port Mode
dot1x ipv6 passthrough
no dot1x ipv6 passthrough
Enables IPv6 passthrough function of global mode on a
switch, only applicable when access control mode is
userbased; the no operation of this command will disable
the function.
3. Supplicant related property configuration
Command Explanation
Global Mode
dot1x max-req <count>
no dot1x max-req
Sets the number of EAP request/MD5 frame to be sent
before the switch re-initials authentication on no supplicant
response, the no command restores the default setting.
dot1x re-authentication
no dot1x re-authentication
Enables periodical supplicant authentication; the no
command disables this function.
dot1x timeout quiet-period
<seconds>
no dot1x timeout
quiet-period
Sets time to keep silent on port authentication failure; the
no command restores the default value.
dot1x timeout re-authperiod
<seconds>
no dot1x timeout
re-authperiod
Sets the supplicant re-authentication interval; the no
command restores the default setting.
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dot1x timeout tx-period
<seconds>
no dot1x timeout tx-period
Sets the interval for the supplicant to re-transmit EAP
request/identity frame; the no command restores the
default setting.
dot1x re-authenticate
[interface <interface-name> ]
Enables IEEE 802.1x re-authentication (no wait timeout
requires) for all ports or a specified port.
42.3 802.1x Application Example
42.3.1 Examples of Guest VLAN Applications
Update server Authenticator server
Ethernet1/3
VLAN10 VLAN2
SWITCHEthernet1/2
Ethernet1/6 VLAN100
VLAN5 Internet
User
Figure 42-13: The Network Topology of Guest VLAN
Notes: In the figures in this session, E2 means Ethernet 1/2, E3 means Ethernet 1/3 and E6
means Ethernet 1/6.
As shown in the next figure, a switch accesses the network using 802.1x authentication, with a
RADIUS server as its authentication server. Ethernet1/2, the port through which the user
accesses the switch belongs to VLAN100; the authentication server is in VLAN2; Update
Server, being in VLAN10, is for the user to download and update supplicant system software;
Ethernet1/6, the port used by the switch to access the Internet is in VLAN5.
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Figure 42-14: User Joining Guest VLAN
As illustrated in the above figure, on the switch port Ethernet1/2, the 802.1x feature is enabled,
and the VLAN10 is set as the port’s Guest VLAN. Before the user gets authenticated or when
the user fails to do so, port Ethernet1/2 is added to VLAN10, allowing the user to access the
Update Server.
Figure 42-15: User Being Online, VLAN Being Offline
As illustrated in the above figure, when the users are online after a successful authentication,
the authentication server will assign VLAN5, which makes both the user and Ethernet1/6 in
VLAN5, allowing the user to access the Internet.
Internet
SWITCHEthernet1/
2
Ethernet1/3
VLAN10 VLAN2
Update server Authenticator server
Ethernet1/6
VLAN5
User
Update server Authenticator server
VLAN5
User
Ethernet1/6
Ethernet1/3
VLAN10 VLAN2
Ethernet1/
2
SWITCH
Internet
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The following are configuration steps:
# Configure RADIUS server.
Switch(config)#radius-server authentication host 10.1.1.3
Switch(config)#radius-server accounting host 10.1.1.3
Switch(config)#radius-server key test
Switch(config)#aaa enable
Switch(config)#aaa-accounting enable
# Create VLAN100.
Switch(config)#vlan 100
# Enable the global 802.1x function
Switch(config)#dot1x enable
# Enable the 802.1x function on port Ethernet1/2
Switch(config)#interface ethernet1/2
Switch(Config-If-Ethernet1/2)#dot1x enable
# Set the link type of the port as access mode.
Switch(Config-If-Ethernet1/2)#switch-port mode access
# Set the access control mode on the port as portbased.
Switch(Config-If-Ethernet1/2)#dot1x port-method portbased
# Set the access control mode on the port as auto.
Switch(Config-If-Ethernet1/2)#dot1x port-control auto
# Set the port’s Guest VLAN as 100.
Switch(Config-If-Ethernet1/2)#dot1x guest-vlan 100
Switch(Config-If-Ethernet1/2)#exit
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Using the command of show running-config or show interface ethernet1/2, users can
check the configuration of Guest VLAN. When there is no online user, no failed user
authentication or no user gets offline successfully, and more authentication-triggering
messages (EAP-Request/Identity) are sent than the upper limit defined, users can check
whether the Guest VLAN configured on the port takes effect with the command show vlan id
100.
42.3.2 Examples of IPv4 RADIUS Applications
10.1.1.1
10.1.1.2
RADIUS Server
10.1.1.3
Figure 42-16: IEEE 802.1x Configuration Example Topology
The PC is connecting to port 1/2 of the switch; IEEE 802.1x authentication is enabled on
port1/2; the access mode is the default MAC-based authentication. The switch IP address is
10.1.1.2. Any port other than port 1/2 is used to connect to RADIUS authentication server,
which has an IP address of 10.1.1.3, and use the default port 1812 for authentication and port
1813 for accounting. IEEE 802.1x authentication client software is installed on the PC and is
used in IEEE 802.1x authentication.
The configuration procedures are listed below:
Switch(config)#interface vlan 1
Switch(Config-if-vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-vlan1)#exit
Switch(config)#radius-server authentication host 10.1.1.3
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Switch(config)#radius-server accounting host 10.1.1.3
Switch(config)#radius-server key test
Switch(config)#aaa enable
Switch(config)#aaa-accounting enable
Switch(config)#dot1x enable
Switch(config)#interface ethernet 1/2
Switch(Config-Ethernet1/2)#dot1x enable
Switch(Config-Ethernet1/2)#dot1x port-control auto
Switch(Config-Ethernet1/2)#exit
42.3.3 Examples of IPv6 RADIUS Application
2004:1:2:3::2
2004:1:2:3::1 RADIUS Server
2004:1:2:3::3
Figure 42-17: IPv6 RADIUS
Connect the computer to the interface 1/2 of the switch, and enable IEEE802.1x on
interface1/2. Use MAC based authentication. Configure the IP address of the switch as
2004:1:2:3::2, and connect the switch with any interface except interface 1/2 to the RADIUS
authentication server. Configure the IP address of the RADIUS server to be 2004:1:2:3::3. Use
the default ports 1812 and 1813 for authentication and accounting respectively. Install the
IEEE802.1x authentication client software on the computer, and use the client for IEEE802.1x
authentication.
The detailed configurations are listed below:
Switch(config)#interface vlan 1
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Switch(Config-if-vlan1)#ipv6 address 2004:1:2:3::2/64
Switch(Config-if-vlan1)#exit
Switch(config)#radius-server authentication host 2004:1:2:3::3
Switch(config)#radius-server accounting host 2004:1:2:3::3
Switch(config)#radius-server key test
Switch(config)#aaa enable
Switch(config)#aaa-accounting enable
Switch(config)#dot1x enable
Switch(config)#interface ethernet 1/2
Switch(Config-If-Ethernet1/2)#dot1x enable
Switch(Config-If-Ethernet1/2)#dot1x port-control auto
Switch(Config-If-Ethernet1/2)#exit
42.4 802.1x Troubleshooting
It is possible that 802.1x be configured on ports and 802.1x authentication be set to auto, t
switch can’t be to authenticated state after the user runs 802.1x supplicant software. Here are
some possible causes and solutions:
If 802.1x cannot be enabled for a port, make sure the port is not executing MAC binding,
or configured as a port aggregation. To enable the 802.1x authentication, the above
functions must be disabled.
If the switch is configured properly but still cannot pass through authentication,
connectivity between the switch and RADIUS server, the switch and 802.1x client should
be verified, and the port and VLAN configuration for the switch should be checked, too.
Check the event log in the RADIUS server for possible causes. In the event log, not only
unsuccessful logins are recorded, but prompts for the causes of unsuccessful login. If the
event log indicates wrong authenticator password, radius-server key parameter shall be
modified; if the event log indicates no such authenticator, the authenticator needs to be
added to the RADIUS server; if the event log indicates no such login user, the user login
ID and password may be wrong and should be verified and input again.
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Chapter 43 The Number Limitation
Function of MAC and IP in Port, VLAN
Configuration
MAC address list is used to identify the mapping relationship between the destination MAC
addresses and the ports of switch. There are two kinds of MAC addresses in the list: static
MAC address and dynamic MAC address. The static MAC address is set by users, having the
highest priority (will not be overwritten by dynamic MAC address), and will always be effective;
dynamic MAC address is learnt by the switch through transmitting data frames, and will only
be effective in a specific time range. When the switch receives a data framed waiting to be
transmitted, it will study the source MAC address of the data frame, build a mapping
relationship with the receiving port, and then look up the MAC address list for the destination
MAC address. If any matching list entry is found, the switch will transmit the data frame via the
corresponding port, or, the switch will broadcast the data frame over the VLAN it belongs to. If
the dynamically learnt MAC address matches no transmitted data in a long time, the switch will
delete it from the MAC address list.
Usually the switch supports both the static configuration and dynamic study of MAC address,
which means each port can have more than one static set MAC addresses and dynamically
learnt MAC addresses, and thus can implement the transmission of data traffic between port
and known MAC addresses. When a MAC address becomes out of date, it will be dealt with
broadcast. No number limitation is put on MAC address of the ports of our current switches;
every port can have several MAC addressed either by configuration or study, until the
hardware list entries are exhausted. To avoid too many MAC addresses of a port, we should
limit the number of MAC addresses a port can have.
For each INTERFACE VLAN, there is no number limitation of IP; the upper limit of the number
of IP is the upper limit of the number of user on an interface, which is, at the same time, the
upper limit of ARP and ND list entry. There is no relative configuration command can be used
to control the sent number of these list entries. To enhance the security and the controllability
of our products, we need to control the number of MAC address on each port and the number
of ARP, ND on each INTERFACE VLAN. The number of static or dynamic MAC address on a
port should not exceed the configuration. The number of user on each VLAN should not
exceed the configuration, either.
43-96
Limiting the number of MAC and ARP list entry can avoid DOS attack to a certain extent. When
malicious users frequently do MAC or ARP cheating, it will be easy for them to fill the MAC and
ARP list entries of the switch, causing successful DOS attacks.
To sum up, it is very meaningful to develop the number limitation function of MAC and IP in
port, VLAN. Switch can control the number of MAC addresses of ports and the number ARP,
ND list entry of ports and VLAN through configuration commands.
Limiting the number of dynamic MAC and IP of ports:
1. Limiting the number of dynamic MAC. If the number of dynamically learnt MAC address by
the switch is already larger than or equal with the max number of dynamic MAC address, then
shutdown the MAC study function on this port, otherwise, the port can continue its study.
2. Limiting the number of dynamic IP. If the number of dynamically learnt ARP and ND by the
switch is already larger than or equal with the max. number of dynamic ARP and ND, then
shutdown the ARP and ND study function of this port, otherwise, the port can continue its
study.
Limiting the number of MAC, ARP and ND of interfaces:
1. Limiting the number of dynamic MAC. If the number of dynamically learnt MAC address by
the VLAN of the switch is already larger than or equal with the max. number of dynamic MAC
address, then shutdown the MAC study function of all the ports in this VLAN, otherwise, all the
ports in this VLAN can continue their study (except special ports).
2. Limiting the number of dynamic IP. If the number of dynamically learnt ARP and ND by the
switch is already larger than or equal with the max. number of dynamic ARP and ND, then the
VLAN will not study any new ARP or ND, otherwise, the study can be continued.
43.1 The Number Limitation Function of MAC and IP in
Port, VLAN Configuration Task Sequence
1. Enable the number limitation function of MAC and IP on ports
2. Enable the number limitation function of MAC and IP in VLAN
3. Configure the timeout value of querying dynamic MAC
4. Configure the violation mode of ports
5. Display and debug the relative information of number limitation of MAC and IP on ports
43-97
1. Enable the number limitation function of MAC and IP on ports
Command Explanation
Port Mode
switchport mac-address dynamic
maximum <value>
no switchport mac-address dynamic
maximum
Enable and disable the number limitation
function of MAC on the ports.
switchport arp dynamic maximum <value>
no switchport arp dynamic maximum
Enable and disable the number limitation
function of ARP on the ports.
switchport nd dynamic maximum <value>
no switchport nd dynamic maximum
Enable and disable the number limitation
function of ND on the ports.
2. Enable the number limitation function of MAC and IP in VLAN
Command Explanation
VLAN Mode
vlan mac-address dynamic maximum
<value>
no vlan mac-address dynamic maximum
Enable and disable the number limitation
function of MAC in the VLAN.
VLAN Interface Mode
ip arp dynamic maximum <value>
no ip arp dynamic maximum
Enable and disable the number limitation
function of ARP in the VLAN.
ipv6 nd dynamic maximum <value>
no ipv6 nd dynamic maximum
Enable and disable the number limitation
function of NEIGHBOR in the VLAN.
3. Configure the timeout value of querying dynamic MAC
Command Explanation
Global Mode
mac-address query timeout <seconds> Configure the timeout value of querying
dynamic MAC.
4. Configure the violation mode of ports
Command Explanation
Port Mode
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switchport mac-address violation {protect
| shutdown} [recovery <5-3600>]
no switchport mac-address violation
Set the violation mode of the port, the no
command restores the violation mode to
protect.
5. Display and debug the related information of number limitation of MAC and IP on
ports
Command Explanation
Admin Mode
show mac-address dynamic count {vlan
<vlan-id> | interface ethernet
<portName> }
Display the number of dynamic MAC in
corresponding ports and VLAN.
show arp-dynamic count {vlan
<vlan-id> | interface ethernet
<portName> }
Display the number of dynamic ARP in
corresponding ports and VLAN.
show nd-dynamic count {vlan
<vlan-id> | interface ethernet
<portName> }
Display the number of dynamic
NEIGHBOUR in corresponding ports and
VLAN.
debug switchport mac count
no debug switchport mac count
All kinds of debug information when
limiting the number of MAC on ports.
debug switchport arp count
no debug switchport arp count
All kinds of debug information when
limiting the number of ARP on ports.
debug switchport nd count
no debug switchport nd count
All kinds of debug information when
limiting the number of NEIGHBOUR on
ports.
debug vlan mac count
no debug vlan mac count
All kinds of debug information when
limiting the number of MAC in VLAN.
debug ip arp count
no debug ip arp count
All kinds of debug information when
limiting the number of ARP in VLAN.
debug ipv6 nd count
no debug ipv6 nd count
All kinds of debug information when
limiting the number of MAC in VLAN.
43-99
43.2 The Number Limitation Function of MAC and IP in
Port, VLAN Typical Examples
SWITCH A
SWITCH B
………
PC PC PC PC PC
Figure 43-1: The Number Limitation of MAC and IP in Port, VLAN Typical Configuration
Example
g successful DOS attacks. Limiting the MAC, ARP, ND list entry can
revent DOS attack.
of
ynamic MAC address as 30, of dynamic ARP address as 30, NEIGHBOR list entry as 20.
WITCH A configuration task sequence:
imum 20
Switch (Config-if-Vlan1)#vlan mac-address dynamic maximum 30
In the network topology above, SWITCH B connects to many PC users, before enabling the
number limitation function of MAC and IP in Port, VLAN, if the system hardware has no other
limitation, SWTICH A and SWTICH B can get the MAC, ARP, ND list entries of all the PC, so
limiting the MAC, ARP list entry can avoid DOS attack to a certain extent. When malicious
users frequently do MAC, ARP cheating, it will be easy for them to fill the MAC, ARP list entries
of the switch, causin
p
On port 1/1 of SWITCH A, set the max. number can be learnt of dynamic MAC address as 20,
dynamic ARP address as 20, NEIGHBOR list entry as 10. In VLAN 1, set the max. number
d
S
Switch (config)#interface ethernet 1/1
Switch (Config-If-Ethernet1/1)#switchport mac-address dynamic max
Switch (Config-If-Ethernet1/1)#switchport arp dynamic maximum 20
Switch (Config-If-Ethernet1/1)#switchport nd dynamic maximum 10
43-100
43.3 The Number Limitation Function of MAC and IP in
Port, VLAN Troubleshooting Help
The number limitation function of MAC and IP in Port, VLAN is disabled by default, if users
need to limit the number of user accessing the network, they can enable it. If the number
limitation function of MAC address can not be configured, please check whether Spanning-tree,
dot1x, TRUNK is running on the switch and whether the port is configured as a MAC-binding
port. The number limitation function of MAC address is mutually exclusive to these
configurations, so if the users need to enable the number limitation function of MAC address
on the port, they should check these functions mentioned above on this port are disabled.
If all the configurations are normal, after enabling the number limitation function of MAC and IP
in Port, VLAN, users can use debug commands to debug every limitation, check the details of
number limitations and judge whether the number limitation function is correct. If there is any
problem, please sent result to technical service center.
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Chapter 44 Operational Configuration
of AM Function
44.1 Introduction to AM Function
AM (Access Management) means that when a switch receives an IP or ARP message, it will
compare the information extracted from the message (such as source IP address or source
MAC-IP address) with the configured hardware address pool. If there is an entry in the address
pool matching the information (source IP address or source MAC-IP address), the message
will be forwarded, otherwise, dumped. The reason why source-IP-based AM should be
supplemented by source-MAC-IP-based AM is that IP address of a host might change. Only
with a bound IP, can users change the IP of the host into forwarding IP, and hence enable the
messages from the host to be forwarded by the switch. Given the fact that MAC-IP can be
exclusively bound with a host, it is necessary to make MAC-IP bound with a host for the
purpose of preventing users from maliciously modifying host IP to forward the messages from
their hosts via the switch.
With the interface-bound attribute of AM, network mangers can bind the IP (MAC-IP) address
of a legal user to a specified interface. After that, only the messages sending by users with
specified IP (MAC-IP) addresses can be forwarded via the interface, and thus strengthen the
monitoring of the network security.
44.2 AM Function Configuration Task List
1. Enable AM function
2. Enable AM function on an interface
3. Configure the forwarding IP
4. Configure the forwarding MAC-IP
5. Delete all of the configured IP or MAC-IP or both
6. Display relative configuration information of AM
1. Enable AM function
Command Explanation
44-102
Global Mode
am enable
no am enable Globally enable or disable AM function.
2. Enable AM function on an interface
Command Explanation
Port Mode
am port
no am port
Enable/disable AM function on the port.
When the AM function is enabled on the
port, no IP or ARP message will be
forwarded by default.
3. Configure the forwarding IP
Command Explanation
Port Mode
am ip-pool <ip-address> <num>
no am ip-pool <ip-address> <num> Configure the forwarding IP of the port.
4. Configure the forwarding MAC-IP
Command Explanation
Port Mode
am mac-ip-pool <mac-address>
<ip-address>
no am mac-ip-pool <mac-address>
<ip-address>
Configure the forwarding MAC-IP of the
port.
5. Delete all of the configured IPs or MAC-IPs or both
Command Explanation
Global Mode
no am all [ip-pool|mac-ip-pool]
Delete MAC-IP address pool or IP
address pool or both pools configured by
all users.
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6. Display related configuration information of AM
Command Explanation
Global Mode
show am [interface <interface-name>] Display the AM configuration information
of one port or all ports.
44.3 AM Function Example
………
SWITCH
Port2 Port1
Internet
HUB2 HUB1
PC1 PC2 PC30
Figure 44-1: a typical configuration example of AM function
h will only forward data packets from legal users while
umping packets from other users.
ccording to the requirements mentioned above, the switch can be configured as follows:
witch(Config-If-Ethernet 1/1)#am ip-pool 10.10.10.1 10
In the topology above, 30 PCs, after converged by HUB1, connect with interface1 on the
switch. The IP addresses of these 30 PCs range from 100.10.10.1 to 100.10.10.30.
Considering security, the system manager will only take user with an IP address within that
range as legal ones. And the switc
d
A
Switch(config)#am enable
Switch(config)#interface ethernet1/1
Switch(Config-If-Ethernet 1/1)#am port
S
44-104
44.4 AM Function Troubleshooting
AM function is disabled by default, and after it is enabled, related configuration of AM can be
not, and AM information on each interface, they can also use “show am
nterface <interface-name>]” command to check the AM configuration information on a
any operational error happens, the system will display detailed corresponding prompt.
made.
Users can view the current AM configuration with “show am” command, such as whether the
AM is enabled or
[i
specific interface.
If
44-105
Chapter 45 Security Feature
Configuration
45.1 Introduction to Security Feature
Before introducing the security features, we here first introduce the DoS. The DoS is short for
Denial of Service, which is a simple but effective destructive attack on the internet. The server
under DoS attack will drop normal user data packet due to non-stop processing the attacker’s
data packet, leading to the denial of the service and worse can lead to leak of sensitive data of
the server.'
Security feature refers to applications such as protocol check which is for protecting the server
from attacks such as DoS. The protocol check allows the user to drop matched packets based
on specified conditions. The security features provide several simple and effective protections
against Dos attacks while acting no influence on the linear forwarding performance of the
switch.
45.2 Security Feature Configuration
45.2.1 Prevent IP Spoofing Function Configuration
Task Sequence
1．Enable the IP spoofing function.
Command Explanation
Global Mode
[no] dosattack-check srcip-equal-dstip
enable
Enable/disable the function of checking if the
IP source address is the same as the
destination address.
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45.2.2 Prevent TCP Unauthorized Label Attack
Function Configuration Task Sequence
1．Enable the anti TCP unauthorized label attack function
Command Explanation
Global Mode
[no] dosattack-check tcp-flags enable Enable/disable checking TCP label function.
45.2.3 Anti Port Cheat Function Configuration Task
Sequence
1． Enable the anti port cheat function
Command Explanation
Global Mode
[no] dosattack-check
srcport-equal-dstport enable Enable/disable the prevent-port-cheat function.
45.2.4 Prevent TCP Fragment Attack Function
Configuration Task Sequence
1．Enable the prevent TCP fragment attack function
2．Configure the minimum permitted TCP head length of the packet
Command Explanation
Global Mode
[no] dosattack-check tcp-fragment
enable
Enable/disable the prevent TCP fragment
attack function.
dosattack-check tcp-header <size>
Configure the minimum permitted TCP head
length of the packet. This command has no
effect when used separately, the user should
enable the dosattack-check tcp-fragment
enable.
Note: This function is not supported by switch.
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45.2.5 Prevent ICMP Fragment Attack Function
Configuration Task Sequence
1. Enable the prevent ICMP fragment attack function
2. Configure the max. permitted ICMPv4 net load length
Command Explanation
Global Mode
[no] dosattack-check icmp-attacking
enable
Enable/disable the prevent ICMP fragment
attack function.
dosattack-check icmpv4-size <size>
Configure the max. permitted ICMPv4 net load
length. This command has not effect when
used separately, the user have to enable the
dosattack-check icmp-attacking enable.
45.3 Security Feature Example
Scenario:
The User has the following configuration requirements: the switch do not forward data packet
whose source IP address is equal to the destination address, and those whose source port is
equal to the destination port. Only the ping command with defaulted options is allowed within
the IPv4 network, namely the ICMP request packet can not be fragmented and its net length is
normally smaller than 100.
Configuration procedure:
Switch(config)# dosattack-check srcip-equal-dstip enable
Switch(config)# dosattack-check srcport-equal-dstport enable
Switch(config)# dosattack-check icmp-attacking enable
Switch(config)# dosattack-check icmpV4-size 100
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Chapter 46 TACACS+ Configuration
46.1 Introduction to TACACS+
TACACS+ terminal access controller access control protocol is a protocol similar to the radius
protocol for control the terminal access to the network. Three independent functions of
Authentication, Authorization, Accounting are also available in this protocol. Compared with
RADIUS, the transmission layer of TACACS+ protocol is adopted with TCP protocol, further
with the packet head ( except for standard packet head) encryption, this protocol is of a more
reliable transmission and encryption characteristics, and is more adapted to security control.
According to the characteristics of the TACACS+ (Version 1.78), we provide TACACS+
authentication function on the switch, when the user logs, such as telnet, the authentication of
user name and password can be carried out with TACACS+.
46.2 TACACS+ Configuration Task List
1. Configure the TACACS+ authentication key
2. Configure the TACACS+ server
3. Configure the TACACS+ authentication timeout time
4. Configure the IP address of the RADIUS NAS
1. Configure the TACACS+ authentication key
Command Explanation
Global Mode
tacacs-server key {0 | 7}<string>
no tacacs-server key
Configure the TACACS+ server key; the
“no tacacs-server key” command deletes
the key.
2. Configure TACACS+ server
Command Explanation
Global Mode
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tacacs-server authentication host
<ip-address> [port <port-number>]
[timeout <seconds>] [key {0 | 7}
<string>] [primary]
no tacacs-server authentication host
<ip-address>
Configure the IP address, listening port
number, the value of timeout timer and the
key string of the TACACS+ server; the no
form of this command deletes the
TACACS+ authentication server.
3. Configure the TACACS+ authentication timeout time
Command Explanation
Global Mode
tacacs-server timeout <seconds>
no tacacs-server timeout
Configure the authentication timeout for the
TACACS+ server, the “no tacacs-server
timeout” command restores the default
configuration.
4. Configure the IP address of the TACACS+ NAS
Command Explanation
Global Mode
tacacs-server nas-ipv4 <ip-address>
no tacacs-server nas-ipv4
To configure the source IP address for the
TACACS+ packets for the switch.
46.3 TACACS+ Scenarios Typical Examples
10.1.1.2
10.1.1.1 TACACS
Server
10 1 1 3
Figure 46-1: TACACS Configuration
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A computer connects to a switch, of which the IP address is 10.1.1.2 and connected with a
TACACS+ authentication server; IP address of the server is 10.1.1.3 and the authentication
port is defaulted at 49, set telnet log on authentication of the switch as tacacs local, via using
TACACS+ authentication server to achieve telnet user authentication.
Switch(config)#interface vlan 1
Switch(Config-if-vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-vlan1)#exit
Switch(config)#tacacs-server authentication host 10.1.1.3
Switch(config)#tacacs-server key test
Switch(config)#authentication line vty login tacacs
46.4 TACACS+ Troubleshooting
In configuring and using TACACS+, the TACACS+ may fail to authentication due to reasons
such as physical connection failure or wrong configurations. The user should ensure the
following:
First good condition of the TACACS+ server physical connection.
Second all interface and link protocols are in the UP state (use “show interface”
command).
Then ensure the TACACS+ key configured on the switch is in accordance with the one
configured on TACACS+ server.
Finally ensure to connect to the correct TACACS+ server.
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Chapter 47 RADIUS Configuration
47.1 Introduction to RADIUS
47.1.1 AAA and RADIUS Introduction
AAA is short for Authentication, Authorization and Accounting. it provideS a consistent
framework for the network management safely. According to the three functions of
Authentication, Authorization, Accounting, the framework can meet the access control for the
security network in which one can visit the network device and the access-level the user can
have and the accounting for the network resource.
RADIUS (Remote Authentication Dial in User Service), is a kind of distributed and client/server
protocol for information exchange. The RADIUS client is usually used on network appliance to
implement AAA in cooperation with 802.1x protocol. The RADIUS server maintains the
database for AAA, and communicates with the RADIUS client through RADIUS protocol. The
RADIUS protocol is the most common used protocol in the AAA framework.
47.1.2 Message Structure for RADIUS
The RADIUS protocol uses UDP to deliver protocol packets. The packet format is shown
below.
Figure 47-1: Message structure for RADIUS
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Code field (1octets) is the type of the RADIUS packet. Available value for the Code field is
shown below:
1 Access-Request
2 Access-Accept
3 Access-Reject
4 Accounting-Request
5 Accounting-Response
11 Access-Challenge
Identifier field (1 octet): Identifier for the request and answer packets.
Length field (2 octets): The length of the overall RADIUS packet, including Code, Identifier,
Length, Authenticator and Attributes
Authenticator field (16 octets): used for validation of the packets received from the RADIUS
server. Or it can be used to carry encrypted passwords. This field falls into two kinds: the
Request Authenticator and the Response Authenticator.
Attribute field: used to carry detailed information about AAA. An Attribute value is formed by
Type, Length, and Value fields.
Type field (1 octet), the type of the attribute value, which is shown as below:
Property Type of property Property Type of property
1 User-Name 23 Framed-IPX-Network
2 User-Password 24 State
3 CHAP-Password 25 Class
4 NAS-IP-Address 26 Vendor-Specific
5 NAS-Port 27 Session-Timeout
6 Service-Type 28 Idle-Timeout
7 Framed-Protocol 29 Termination-Action
8 Framed-IP-Address 30 Called-Station-Id
9 Framed-IP-Netmask 31 Calling-Station-Id
10 Framed-Routing 32 NAS-Identifier
11 Filter-Id 33 Proxy-State
12 Framed-MTU 34 Login-LAT-Service
13 Framed-Compression 35 Login-LAT-Node
14 Login-IP-Host 36 Login-LAT-Group
15 Login-Service 37 Framed-AppleTalk-Link
16 Login-TCP-Port 38 Framed-AppleTalk-Network
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17 (unassigned) 39 Framed-AppleTalk-Zone
18 Reply-Message 40-59 (reserved for accounting)
19 Callback-Number 60 CHAP-Challenge
20 Callback-Id 61 NAS-Port-Type
21 (unassigned) 62 Port-Limit
22 Framed-Route 63 Login-LAT-Port
Length field (1 octet), the length in octets of the attribute including Type, Length and
Value fields.
Value field, value of the attribute whose content and format is determined by the type and
length of the attribute.
47.2 RADIUS Configuration Task List
1. Enable the authentication and accounting function
2. Configure the RADIUS authentication key
3. Configure the RADIUS server
4. Configure the parameter of the RADIUS service
5. Configure the IP address of the RADIUS NAS
1. Enable the authentication and accounting function
Command Explanation
Global Mode
aaa enable
no aaa enable
To enable the AAA authentication function.
The no form of this command will disable
the AAA authentication function.
aaa-accounting enable
no aaa-accounting enable
To enable AAA accounting. The no form of
this command will disable AAA accounting.
aaa-accounting update {enable|disable} Enable or disable the update accounting
function.
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2. Configure the RADIUS authentication key
Command Explanation
Global Mode
radius-server key {0 | 7} <string>
no radius-server key
To configure the encryption key for the
RADIUS server. The no form of this
command will remove the configured key.
3. Configure the RADIUS server
Command Explanation
Global Mode
radius-server authentication host
{<ipv4-address> | <ipv6-address>} [port
<port-number>] [key {0 | 7} <string>]
[primary] [access-mode {dot1x | telnet}]
no radius-server authentication host
{<ipv4-address> | <ipv6-address>
Specifies the IPv4/IPv6 address and the
port number, whether be primary server for
RADIUS accounting server; the no
command deletes the RADIUS accounting
server.
radius-server accounting host
{<ipv4-address> | <ipv6-address>} [port
<port-number>] [key {0 | 7} <string>]
[primary]
no radius-server accounting host
{<ipv4-address> | <ipv6-address>}
Specifies the IPv4/IPv6 address and the
port number, whether be primary server for
RADIUS accounting server; the no
command deletes the RADIUS accounting
server.
4. Configure the parameter of the RADIUS service
Command Explanation
Global Mode
radius-server dead-time <minutes>
no radius-server dead-time
To configure the interval that the RADIUS
becomes available after it is down. The no
form of this command will restore the
default configuration.
radius-server retransmit <retries>
no radius-server retransmit
To configure retry times for the RADIUS
packets. The no form of this command
restores the default configuration.
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radius-server timeout <seconds>
no radius-server timeout
To configure the timeout value for the
RADIUS server. The no form of this
command will restore the default
configuration.
radius-server accounting-interim-update
timeout <seconds>
no radius-server
accounting-interim-update timeout
To configure the update interval for
accounting. The no form of this command
will restore the default configuration.
5. Configure the IP address of the RADIUS NAS
Command Explanation
Global Mode
radius nas-ipv4 <ip-address>
no radius nas-ipv4
To configure the source IP address for the
RADIUS packets for the switch.
radius nas-ipv6 <ipv6-address>
no radius nas-ipv6
To configure the source IPv6 address for
the RADIUS packets for the switch.
47.3 RADIUS Typical Examples
47.3.1 IPv4 RADIUS Example
10.1.1.2
10.1.1.1 RADIUS Server
10.1.1.3
Figure 47-2: The Topology of IEEE802.1x configuration
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A computer connects to a switch, of which the IP address is 10.1.1.2 and connected with a
RADIUS authentication server without Ethernet1/2; IP address of the server is 10.1.1.3 and
the authentication port is defaulted at 1812, accounting port is defaulted at 1813.
Configure steps as below:
Switch(config)#interface vlan 1
Switch(Config-if-vlan1)#ip address 10.1.1.2 255.255.255.0
Switch(Config-if-vlan1)#exit
Switch(config)#radius-server authentication host 10.1.1.3
Switch(config)#radius-server accounting host 10.1.1.3
Switch(config)#radius-server key test
Switch(config)#aaa enable
Switch(config)#aaa-accounting enable
47.3.2 IPv6 RADIUS Example
2004:1:2:3::2
2004:1:2:3::1 RADIUS Server
2004:1:2:3::3
Figure 47-3: The Topology of IPv6 RADIUS configuration
A computer connects to a switch, of which the IP address is 2004:1:2:3::2 and connected with
a RADIUS authentication server without Ethernet1/2; IP address of the server is 2004:1:2:3::3
and the authentication port is defaulted at 1812, accounting port is defaulted at 1813.
Configure steps as shown below:
Switch(config)#interface vlan 1
Switch(Config-if-vlan1)#ipv6 address 2004:1:2:3::2/64
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Switch(Config-if-vlan1)#exit
Switch(config)#radius-server authentication host 2004:1:2:3::3
Switch(config)#radius-server accounting host 2004:1:2:3::3
Switch(config)#radius-server key test
Switch(config)#aaa enable
Switch(config)#aaa-accounting enable
47.4 RADIUS Troubleshooting
In configuring and using RADIUS, the RADIUS may fail to authentication due to reasons such
as physical connection failure or wrong configurations. The user should ensure the following:
First make sure good condition of the RADIUS server physical connection
Second all interface and link protocols are in the UP state (use “show interface”
command)
Then ensure the RADIUS key configured on the switch is in accordance with the one
configured on RADIUS server
Finally ensure to connect to the correct RADIUS server
If the RADIUS authentication problem remains unsolved, please use debug aaa and other
debugging command and copy the DEBUG message within 3 minutes, send the recorded
message to the technical server center of our company.
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Chapter 48 SSL Configuration
48.1 Introduction to SSL
As the computer networking technology spreads, the security of the network has been taking
more and more important impact on the availability and the usability of the networking
application. The network security has become one of the greatest barriers of modern
networking applications.
To protect sensitive data transferred through Web, Netscape introduced the Secure Socket
Layer – SSL protocol, for its Web browser. Up till now, SSL 2.0 and 3.0 has been released.
SSL 2.0 is obsolete because of security problems, and it is not supported on the switches of
Network. The SSL protocol uses the public-key encryption, and has become the industry
standard for secure communication on internet for Web browsing. The Web browser integrates
HTTP and SSL to realize secure communication.
SSL is a safety protocol to protect private data transmission on the Internet. SSL protocols are
designed for secure transmission between the client and the server, and authentication both at
the server sides and optional client. SSL protocols must build on reliable transport layer (such
as TCP). SSL protocols are independent for application layer. Some protocols such as HTTP,
FTP, TELNET and so on, can build on SSL protocols transparently. The SSL protocol
negotiates for the encryption algorithm, the encryption key and the server authentication
before data is transmitted. Ever since the negotiation is done, all the data being transferred will
be encrypted.
Via above introduction, the security channel is provided by SSL protocols have below three
characteristics:
Privacy. First they encrypt the suite through negotiation, then all the messages be
encrypted.
Affirmation. Though the client authentication of the conversational is optional, but the
server is always authenticated.
Reliability. The message integrality inspect is included in the sending message (use
MAC).
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48.1.1 Basic Element of SSL
The basic strategy of SSL provides a safety channel for random application data forwarding
between two communication programs. In theory, SSL connect is similar with encrypt TCP
connect. The position of SSL protocol is under application layer and on the TCP. If the
mechanism of the data forwarding in the lower layer is reliable, the data read-in the network
will be forwarded to the other program in sequence, lose packet and re-forwarding will not
appear. A lot of transmission protocols can provide such kind of service in theory, but in actual
application, SSL is almost running on TCP, and not running on UDP and IP directly.
When web function is running on the switch and client visit our web site through the internet
browser, we can use SSL function. The communication between client and switch through SSL
connect can improve the security.
Firstly, SSL should be enabled on the switch. When the client tries to access the switch
through https method, a SSL session will be set up between the switch and the client. When
the SSL session has been set up, all the data transmission in the application layer will be
encrypted.
SSL handshake is done when the SSL session is being set up. The switch should be able to
provide certification keys. Currently the keys provided by the switch are not the formal
certification keys issued by official authentic, but the private certification keys generated by
SSL software under Linux which may not be recognized by the web browser. With regard to
the switch application, it is not necessary to apply for a formal SSL certification key. A private
certification key is enough to make the communication safe between the users and the switch.
Currently it is not required that the client is able to check the validation of the certification key.
The encryption key and the encryption method should be negotiated during the handshake
period of the session which will be then used for data encryption.
SSL session handshake process:
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48.2 SSL Configuration Task List
1. Enable/disable SSL function
2. Configure/delete port number by SSL used
3. Configure/delete secure cipher suite by SSL used
4. Maintenance and diagnose for the SSL function
1. Enable/disable SSL function
Command Explanation
Global Mode
ip http secure-server
no ip http secure-server Enable/disable SSL function.
2. Configure/delete port number by SSL used
Command Explanation
Global Mode
ip http secure-port <port-number>
no ip http secure-port
Configure port number by SSL used, the“no
ip http secure-port” command deletes the
port number.
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3. Configure/delete secure cipher suite by SSL used
Command Explanation
Global Mode
ip http secure-ciphersuite
{des-cbc3-sha|rc4-128-sha|
des-cbc-sha}
no ip http secure-ciphersuite
Configure/delete secure cipher suite by SSL
used.
4. Maintenance and diagnose for the SSL function
Command Explanation
Admin Mode
show ip http secure-server status Show the configured SSL information.
debug ssl
no debug ssl Open/close the DEBUG for SSL function.
48.3 SSL Typical Example
When the Web function is enabled on the switch, SSL can be configured for users to access
the web interface on the switch. If the SSL has been configured, communication between the
client and the switch will be encrypted through SSL for safety.
Firstly, SSL should be enabled on the switch. When the client tries to access the switch
through https method, a SSL session will be set up between the switch and the client. When
the SSL session has been set up, all the data transmission in the application layer will be
encrypted.
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Web Server
Malicious Users
PC Users
Date Acquisition Fails
Web Browser https
SSLSession
Connected
Configuration on the switch:
Switch(config)# ip http secure-server
Switch(config)# ip http secure-port 1025
Switch(config)# ip http secure-ciphersuite rc4-128-sha
48.4 SSL Troubleshooting
In configuring and using SSL, the SSL function may fail due to reasons such as physical
connection failure or wrong configurations. The user should ensure the following:
First good condition of the physical connection;
Second all interface and link protocols are in the UP state (use “show interface”
command);
Then, make sure SSL function is enabled (use ip http secure-server command );
Don’t use the default port number if configured port number, pay attention to the port
number when input the web wide;
If SSL is enabled, SSL should be restarted after changes on the port configuration and
encryption configuration;
IE 7.0 or above should be used for use of des-cbc-sha;
If the SSL problems remain unsolved after above try, please use debug SSL and other
debugging command and copy the DEBUG message within 3 minutes, send the
recorded message to technical server center of our company.
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Chapter 49 IPv6 Security RA
Configuration
49.1 Introduction to IPv6 Security RA
In IPv6 networks, the network topology is generally compromised of routers, layer-two
switches and IPv6 hosts. Routers usually advertise RA, including link prefix, link MTU and
other information, when the IPv6 hosts receive RA, they will create link address, and set the
default router as the one sending RA in order to implement IPv6 network communication. If a
vicious IPv6 host sends RA to cause that normal IPv6 users set the default router as the
vicious IPv6 host user, the vicious user will be able to capture the information of other users,
which will threat the network security. Simultaneously, the normal users get incorrect address
and will not be able to connect to the network. So, in order to implement the security RA
function, configuring on the switch ports to reject vicious RA messages is necessary, thus to
prevent forwarding vicious RA to a certain extent and to avoid affecting the normal operation of
the network.
49.2 IPv6 Security RA Configuration Task Sequence
1. Globally enable IPv6 security RA
2. Enable IPv6 security RA on a port
3. Display and debug the relative information of IPv6 security RA
1. Globally enable IPv6 security RA
Command Explanation
Global Mode
ipv6 security-ra enable
no ipv6 security-ra enable
Globally enable and disable IPv6 security
RA.
2. Enable IPv6 security RA on a port
Command Explanation
Port Mode
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ipv6 security-ra enable
no ipv6 security-ra enable
Enable and disable IPv6 security RA in port
configuration mode.
3. Display and debug the related information of IPv6 security RA
Command Explanation
Admin Mode
debug ipv6 security-ra
no debug ipv6 security-ra
Enable the debug information of IPv6
security RA module, the no operation of
this command will disable the output of
debug information of IPv6 security RA.
show ipv6 security-ra [interface
<interface-list>]
Display the untrusted port and whether
globally security RA is enabled.
49.3 IPv6 Security RA Typical Examples
Other IPv6 network
PC User
RA Ethernet1/1
Ethernet1/2
RA
X
Ethernet1/3
Illegal User
Figure 49-1: IPv6 Security RA sketch map
Instructions: if the illegal user in the graph advertises RA, the normal user will receive the RA,
set the default router as the vicious IPv6 host user and change its own address. This will cause
the normal user to not be able to connect the network. We want to set security RA on the 1/2
port of the switch, so that the RA from the illegal user will not affect the normal user.
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Switch configuration task sequence:
Switch#config
Switch(config)#ipv6 security-ra enable
Switch(Config-If-Ethernet1/2)# ipv6 security-ra enable
49.4 IPv6 Security RA Troubleshooting Help
The function of IPv6 security RA is quite simple, if the function does not meet the expectation
after configuring IPv6 security RA:
Check if the switch is correctly configured.
Check if there are rules conflicting with security RA function configured on the switch,
this kind of rules will cause RA messages to be forwarded.
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Chapter 50 MAB Configuration
50.1 Introduction to MAB
In actual network, the existing device cannot install the authentication client, such as printer,
and PDA devices, and cannot process 802.1x authentication. However, to access the network
resources, they need to use MAB authentication to replace 802.1x authentication.
MAB authentication is a network accessing authentication method based on the accessing
port and the MAC address of MAB user. The user needn’t install any authentication client, after
the authentication device receives ARP packets sent by MAB user, it will authenticate the MAC
address of the MAB user and there is the corresponding authentication information in the
authentication server, the matched packets of the port and the source MAC are allowed to
pass when the authentication is successful. MAB user didn’t need to input the username and
password manually in the process of authentication.
At present, MAB authentication device only supports RADIUS authentication method. There is
the selection method for the authentication username and password: use the MAC address of
the MAB user as the username and password, or the fixed username and password (all users
use the configured username and password to authenticate).
50.2 MAB Configuration Task List
MAB Configuration Task List:
1. Enable MAB function
1) Enable global MAB function
2) Enable port MAB function
2. Configure MAB authentication username and password
3. Configure MAB parameters
1) Configure guest-vlan
2) Configure the binding-limit of the port
3) Configure the reauthentication time
4) Configure the offline detection time
5) Configure other parameters
1. Enable MAB function
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Command Explanation
Global Mode
mac-authentication-bypass enable
no mac-authentication-bypass enable
Enable the global MAB authentication
function.
Port Mode
mac-authentication-bypass enable
no mac-authentication-bypass enable
Enable the port MAB authentication
function.
2. Configure MAB authentication username and password
Command Explanation
Global Mode
mac-authentication-bypass
username-format {mac-address | {fixed
username WORD password WORD}}
Set the authentication mode of MAB
authentication function.
3. Configure MAB parameters
Command Explanation
Port Mode
mac-authentication-bypass
binding-limit <1-100>
no mac-authentication-bypass
binding-limit
Set the max. MAB binding-limit of the port.
Global Mode
mac-authentication-bypass timeout
offline-detect （0｜<60-7200>）
no mac-authentication-bypass timeout
offline-detect
Set offline detection interval.
mac-authentication-bypass timeout
quiet-period <1-60>
no mac-authentication-bypass timeout
quiet-period
Set quiet-period of MAB authentication.
mac-authentication-bypass timeout
stale-period <0-60>
no mac-authentication-bypass timeout
stale-period
Set the time that delete the binding after the
port is down.
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mac-authentication-bypass
spoofing-garp-check enable
no mac-authentication-bypass
spoofing-garp-check enable
Enable the spoofing-garp-check function,
MAB function will not deal with
spoofing-garp any more; the no command
disables the function.
authentication mab {radius | none}
no authentication mab
Configure the authentication mode and
priority of MAC address, the no command
restores the default authentication mode.
50.3 MAB Example
Example:
The typical example of MAB authentication function:
Update Server Radius Server Internet
Eth1/1 Eth1/2 Eth1/3
Switch 1
PC1 PC2 Printer
Switch 2
Eth1/3 Eth1/2 Eth1/1
Ethernet1/4
Ethernet1/4
Figure 50-1: MAB application
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Switch 1 is a layer 2 accessing switch, Switch 2 is a layer 3 aggregation switch.
Ethernet 1/1 is an access port of Switch1, connects to PC1, it enables 802.1x port-based
function and configures guest vlan as vlan8.
Ethernet 1/2 is a hybrid port, connects to PC2, native vlan of the port is vlan1, and configures
guest vlan as vlan8, it joins in vlan1, vlan8 and vlan10 with untag method and enables MAB
function.
Ethernet 1/3 is an access port, connects to the printer and enables MAB function.
Ethernet 1/4 is a trunk port, connects to Switch 2.
Ethernet 1/4 is a trunk port of Switch 2, connects to Switch 1.
Ethernet 1/1 is an access port, belongs to vlan8, connects to update server to download and
upgrade the client software.
Ethernet 1/2 is an access port, belongs to vlan9, connects to radius server which configure
auto vlan as vlan10.
Ethernet 1/3 is an access port, belongs to vlan10, connects to external internet resources.
To implement this application, the configuration is as follows:
Switch 1 configuration:
(1) Enable 802.1x and MAB authentication function globally, configure username and
password of MAB authentication and radius-server address
Switch(config)# dot1x enable
Switch(config)# mac-authentication-bypass enable
Switch(config)#mac-authentication-bypass username-format fixed username mabuser
password mabpwd
Switch(config)#vlan 8-10
Switch(config)#interface vlan 9
Switch(config-if-vlan9)ip address 192.168.61.9 255.255.255.0
Switch(config-if-vlan9)exit
Switch(config)#radius-server authentication host 192.168.61.10
Switch(config)#radius-server accounting host 192.168.61.10
Switch(config)#radius-server key test
Switch(config)#aaa enable
Switch(config)#aaa-accounting enable
(2) Enable the authentication function of each port
Switch(config)#interface ethernet 1/1
Switch(config-if-ethernet1/1)#dot1x enable
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Switch(config-if-ethernet1/1)#dot1x port-method portbased
Switch(config-if-ethernet1/1)#dot1x guest-vlan 8
Switch(config-if-ethernet1/1)#exit
Switch(config)#interface ethernet 1/2
Switch(config-if-ethernet1/2)#switchport mode hybrid
Switch(config-if-ethernet1/2)#switchport hybrid native vlan 1
Switch(config-if-ethernet1/2)#switchport hybrid allowed vlan 1;8;10 untag
Switch(config-if-ethernet1/2)#mac-authentication-bypass enable
Switch(config-if-ethernet1/2)#mac-authentication-bypass enable guest-vlan 8
Switch(config-if-ethernet1/2)#exit
Switch(config)#interface ethernet 1/3
Switch(config-if-ethernet1/3)#switchport mode access
Switch(config-if-ethernet1/3)#mac-authentication-bypass enable
Switch(config-if-ethernet1/3)#exit
Switch(config)#interface ethernet 1/4
Switch(config-if-ethernet1/4)# switchport mode trunk
50.4 MAB Troubleshooting
If a problem happens when using MAB function, please check whether the problem is caused
by the following reasons:
Make sure global and port MAB function are enabled;
Make sure the correct username and password of MAB authentication are used;
Make sure the radius-server configuration is correct.
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Chapter 51 PPPoE Intermediate Agent
Configuration
51.1 Introduction to PPPoE Intermediate Agent
51.1.1 Brief Introduction to PPPoE
PPPoE (Point to Point Protocol over Ethernet) is a protocol that applies PPP protocol to
Ethernet. PPP protocol is a link layer protocol that utilizes the communication method of
point-to-point. It is usually selected by host dial-up link, for example, the link is line dial-up.
PPP protocol is applied to Ethernet that means PPPoE protocol makes many hosts of Ethernet
to connect a remote access collector through one or multiple bridge devices. If the remote
access collector is broadband access server (BAS), it can supply broadband access and
accounting functions for these hosts, so PPPoE protocol is used for the broadband access
authentication of Ethernet usually.
51.1.2 Introduction to PPPoE IA
Broadband access technique is rapidly developed. Broadband access network is also
developing from strength to strength, but security problem gradually becomes the focus, so the
clients or the access device and the network are faced with security problem (especially from
the client) in the current access network. Traditional Ethernet user cannot be identified, traced
and located exactly; however, in exoteric and controllable network, identification and location
are the basic character and requirement for user, for example, when supplying the application
that uses user accounts to login, this method supplied by PPPoE Intermediate Agent can avoid
the embezzlement of user accounts.
There are two stages for PPPoE protocol to work: discovery stage and session stage.
Discovery stage is used to obtain MAC address of the remote server to establish a
point-to-point link and a session ID with the server, and session stage uses this session ID to
communicate. PPPoE Intermediate Agent only relates to discovery stage, so we simply
introduce discovery stage.
There are four steps for discovery stage:
1. Client sends PADI packet: For the first step, client uses broadcast address as
destination address and broadcast PADI (PPPoE Active Discovery Initiation) packet
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to discover access collector in layer 2 network. Note: This message may be sent to
many access collectors of the network.
2. Broadband Access Server responds to PADO packet: For the second step, server
responds to PADO (PPPoE Active Discovery Offer) packet to client according to the
received source MAC address of PADI packet; the packet will take server name and
service name.
3. Client sends PADR packet: For the third step, client selects a server to process the
session according to the received PADO packet. It may receive many PADO packets
for PADI. Message of the first step may be sent to many servers (select the server
according to whether the service information of PADO packet matches with the
service information needed by client). MAC address of the other end used for
session will be known after server is selected, and send PADR (PPPoE Active
Discovery Request) packet to it to announce the session requirements of server.
4. Server responds to PADS packet: For the fourth step, server establishes a session
ID according to the received PADR packet. This session ID will be sent to client
through PADS (PPPoE Active Discovery Session-confirmation) packet, hereto
PPPoE discovery stage is completed to enter session stage.
PADT (PPPoE Active Discovery Terminate) packet is a special packet of PPPoE. Its Ethernet
protocol number (0x8863) is the same as the above four packets, so it can be considered a
packet of discovery stage. To stop a PPPoE session, PADT may be sent at the discretional
time of the session. (It can be sent by client or server)
PPPoE Intermediate Agent supplies a function that identifies and locates the user. When
passing network access device, PADI and PADR messages will be sent by client with the
access link tag of this device at PPPoE discovery stage so as to exactly identify and locate the
user on server.
If the direct-link access device is LAN switch, the added information includes: MAC, Slot ID,
Port Index, Vlan ID and so on. This function is implemented according to Migration to
Ethernet-based DSL aggregation.
51.1.2.1 PPPoE Intermediate Agent Exchange Process
PPPoE Intermediate Agent exchange process is similar to PPPoE exchange process, for the
first exchange process, the access link tag is added to PADI and PADR packets. The
exchange process is as follows:
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Figure 51-1: PPPoE IA protocol exchange process
51.1.2.2 PPPoE Packet Format
PPPoE packet format is as follows:
Ethernet II frame
Destination MAC Source MAC Type Field PPPoE Data CRC Check Sum
PPPoE data
Version Type Code Session ID Length Field TLV1 …… TLV N
TLV frame
Type Length Data
The meaning of each field is as follows:
Type field (2 bytes) of Ethernet II frame: The protocol sets type field value of PPPoE protocol
packet as 0x8863 (including 5 kinds of packets in PPPoE discovery stage only), type field
value of session stage as 0x8864.
PPPoE version field (4 bits): Specify the current PPPoE protocol version; the current version
must be set as 0x1.
PPPoE type field (4 bits): Specify the protocol type; the current version must be set as 0x1.
PPPoE code field (1 byte): Specify the packet type; 0x09 means PADI packet, 0x07 means
PADO packet, 0x19 means PADR packet, 0x65 means PADS packet and 0xa7 means PADT
packet.
PPPoE session ID field (2 bytes): Specify the session ID.
PPPoE length field (2 bytes): Specify the sum of all TLV lengths.
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TLV type field (2 bytes): A TLV frame means a TAG and type field means TAG type.
The table is as follows:
TLV length field (2 bytes): Specify the length of TAG data field.
TLV data field (the length is not specified): Specify the transmitted data of TAG.
Tag Type Tag Explanation
0x0000 The end of a series tag in PPPoE data field, it is saved for ensuring the version
compatibility and is applied by some packets.
0x0101 Service name. Indicate the supplied services by network.
0x0102 Server name. When user receives the PADO response packet of AC, it can
obtain the server name from the tag and select the corresponding server.
0x0103 Exclusive tag of the host. It is similar to tag field of PPPoE data packets and is
used to match the sending and receiving end (Because broadcast network may
exist many PPPoE data packets synchronously).
0x0104 AC-Cookies. It is used to avoid the vicious DOS attack.
0x0105 The identifier of vendor.
0x0110 Relay session ID. PPPoE data packet can be interrupted to other AC, this field is
used to keep other connection.
0x0201 The error of service name. When the requested service name is not accepted by
other end, the response packet will take this tag.
0x0202 The error of server name.
0x0203 Common error.
Table 51-1: TAG value type of PPPoE
51.1.2.3 PPPoE Intermediate Agent vendor tag Frame
The following is the format of tag added by PPPoE IA; adding tag is the Uppermost function of
PPPoE IA.
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Figure 51-2: PPPoE IA - vendor tag (4 bytes in each row)
Add TLV tag as 0x0105 for PPPoE IA, TAG_LENGTH is length field of vendor tag;
0x00000DE9 is “ADSL Forum” IANA entry of the fixed 4 bytes; 0x01 is type field of Agent
Circuit ID, length is length field and Agent Circuit ID value field; 0x02 is type field of Agent
Remote ID, length is length field and Agent Remote ID value field.
PPPoE IA supplies a default circuit ID value, the default circuit ID (The figure in the following)
includes 5 fields, ANI (Access Node Identifier) can be configured by user, its length is less than
47 bytes. If there is no ANI configured, MAC is accessed by default, occupy 6 bytes and use
space symbol to compart, “eth” occupies 3 bytes and uses space symbol to compart, “Slot ID”
occupies 2 bytes, use “/” to compart and occupy 1 byte, “Port Index” occupies 3 bytes, use “:”
to compart and occupy 1 byte, “Vlan ID” occupies 4 bytes, all fields use ASCII, user can
configure circuit ID for each port according to requirement.
ANI
(n byte)
Space
( 1byte)
eth
(3 byte)
Space
(1 byte)
Slot ID
(2 byte)
/
(1byte)
Port Index
(3 byte)
:
(1 byte)
Vlan ID
(4 byte)
Figure 51-3: Agent Circuit ID value
MAC of the access switch is the default remote ID value of PPPoE IA. remote ID value can be
configured by user flexibly, the length is less than 63 bytes.
51.1.2.4 Trusted Port of PPPoE Intermediate Agent
Discovery stage sends five kinds of packets, PADI and PADR packets sent by client to server,
PADO and PADS packets sent by server to client, and PADT packet can be sent by server or
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client.
In PPPoE IA, for security and reduced traffic, set a port connected server as trusted port, set
ports connected client as untrusted port, trusted port can receive all packets, untrusted port
can receive only PADI, PADR and PADT packets which are sent to server. To ensure client
operation is correct, it must set the port connecting to server as trusted port. Each access to
device has a trusted port at least.
PPPoE IA vendor tag can not exist in PPPoE packets sent by server to client, so we can strip
and forward these vendor tags if they exist in PPPoE packets. Strip function must be
configured on trusted port, enabling strip function not to take effect on untrusted port.
51.2 PPPoE Intermediate Agent Configuration Task
List
1. Enable global PPPoE Intermediate Agent
2. Enable port PPPoE Intermediate Agent
Command Explanation
Global Mode
pppoe intermediate-agent
no pppoe intermediate-agent
Enable global PPPoE Intermediate Agent
function.
pppoe intermediate-agent type tr-101
circuit-id access-node-id <string>
no pppoe intermediate-agent type tr-101
circuit-id access-node-id
Configure access node ID field value of
circuit ID in added vendor tag.
pppoe intermediate-agent type tr-101
circuit-id identifier-string <string> option
{sp | sv | pv | spv} delimiter <WORD>
[delimiter <WORD> ]
no pppoe intermediate-agent type tr-101
circuit-id identifier-string option delimiter
Configure circuit-id in added vendor tag.
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pppoe intermediate-agent type
self-defined circuit-id {vlan| port|id
(switch-id (mac | hostname)| remote-mac) |
string WORD}
no pppoe intermediate-agent type
self-defined circuit-id
Configure the self-defined circuit-id.
pppoe intermediate-agent type
self-defined remote-id {mac | hostname|
string WORD}
no pppoe intermediate-agent type
self-defined remote-id
Configure the self-defined remote-id.
pppoe intermediate-agent delimiter
<WORD>
no pppoe intermediate-agent delimiter
Configure the delimiter among the fields
in circuit-id and remote-id
pppoe intermediate-agent format
(circuit-id | remote-id) (hex | ascii)
no pppoe intermediate-agent format
(circuit-id | remote-id)
Configure the format with hex or ASCII
for circuit-id and remote-id.
Port Mode
pppoe intermediate-agent
no pppoe intermediate-agent
Enable PPPoE Intermediate Agent
function of port.
pppoe intermediate-agent vendor-tag strip
no pppoe intermediate-agent vendor-tag
strip
Set vendor tag strip function of port.
pppoe intermediate-agent trust
no pppoe intermediate-agent trust Set a port as trusted port.
pppoe intermediate-agent circuit-id
<string>
no pppoe intermediate-agent circuit-id
Set circuit-id of port.
pppoe intermediate-agent remote-id
<string>
no pppoe intermediate-agent remote-id
Set remote-id of port.
51.3 PPPoE Intermediate Agent Typical Application
PPPoE Intermediate Agent typical application is as follows:
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Figure 51-4: PPPoE IA typical application
Both host and BAS server run PPPoE protocol and are connected with Layer 2 Ethernet switch
that enables PPPoE Intermediate Agent function.
Typical configuration (1) in the following:
Step 1: Switch enables global PPPoE IA function, MAC as 0a0b0c0d0e0f.
Switch(config)# pppoe intermediate-agent
Step 2: Configure port ethernet1/1 which connect server as trusted port, and configure vendor
tag strip function.
Switch(config-if-ethernet1/1)#pppoe intermediate-agent trust
Switch(config-if-ethernet1/1)#pppoe intermediate-agent vendor-tag strip
Step 3: Port ethernet1/2 of vlan1 and port ethernet1/3 of vlan 1234 enable PPPoE IA function
of port.
Switch(config-if-ethernet1/2)#pppoe intermediate-agent
Switch(config-if-ethernet1/3)#pppoe intermediate-agent
Step 4: Configure pppoe intermediate-agent access-node-id as abcd.
Switch(config)#pppoe intermediate-agent type tr-101 circuit-id access-node-id abcd
Step 5: Configure circuit ID as aaaa, remote ID as xyz for port ethernet1/3.
Switch(config-if-ethernet1/3)#pppoe intermediate-agent circuit-id aaaa
Switch (config-if-ethernet1/3)#pppoe intermediate-agent remote-id xyz
circuit-id value is ”abcd eth 01/002:0001”, remote-id value is ”0a0b0c0d0e0f” for the
added vendor tag of port ethernet1/2.
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circuit-id value is ”aaaa”, remote-id value is ”xyz” for the added vendor tag of port
ethernet1/3.
Typical configuration (2) in the following:
Step 1: Switch enables global PPPoE IA function, MAC as 0a0b0c0d0e0f.
Switch(config)#pppoe intermediate-agent
Step 2: Configure port ethernet1/1 which connect server as trusted port, and configure vendor
tag strip function.
Switch(config-if-ethernet1/1)#pppoe intermediate-agent trust
Switch(config-if-ethernet1/1)#pppoe intermediate-agent vendor-tag strip
Step 3: Port ethernet1/2 of vlan1 and port ethernet1/3 of vlan 1234 enable PPPoE IA function
of port.
Switch(config-if-ethernet1/2)#pppoe intermediate-agent
Switch(config-if-ethernet1/3)#pppoe intermediate-agent
Step 4: Configure pppoe intermediate-agent access-node-id as abcd.
Switch(config)#pppoe intermediate-agent type tr-101 circuit-id access-node-id abcd
Step 5: Configure pppoe intermediate-agent identifier-string as “efgh”, combo mode as spv,
delimiter of Slot ID and Port ID as “#”, delimiter of Port ID and Vlan ID as “/”.
Switch(config)#pppoe intermediate-agent type tr-101 circuit-id identifier-string efgh option
spv delimiter # delimiter /
Step 6: Configure circuit-id value as bbbb on port ethernet1/2.
Switch(config-if-ethernet1/2)#pppoe intermediate-agent circuit-id bbbb
Step 7: Configure remote-id as xyz on ethernet1/3.
Switch(config-if-ethernet1/3)#pppoe intermediate-agent remote-id xyz
circuit-id value is ”bbbb”, remote-id value is ”0a0b0c0d0e0f” for the added vendor tag of
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port ethernet1/2.
circuit-id value is ”efgh eth 01#003/1234”, remote-id value is ”xyz” for the added vendor
tag of port ethernet1/3.
51.4 PPPoE Intermediate Agent Troubleshooting
Only switch enables global PPPoE intermediate agent firstly, this function can be run on
port.
Configure a trusted port at least, and this port can connect to server.
Vendor tag strip function must be configured by trusted port.
Circuit-id override priority is: pppoe intermediate-agent circuit-id < pppoe
intermediate-agent identifier-string option delimiter < pppoe intermediate-agent
access-node-id.
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Chapter 52 Web Portal Configuration
52.1 Introduction to Web Portal Authentication
802.1x authentication uses the special client to authenticate. The device uses the special layer
2 switch; the authentication server uses RADIUS server; and the format of authentication
message uses EAP protocol. Use EAPOL encapsulation technique (encapsulate EAP packets
within Ethernet frame) to process the communication between client and authentication proxy
switch, but authentication proxy switch and authentication server use EAPOR encapsulation
format (run EAP packets on Radius protocol) to process the communication. The device and
RADIUS server use RADIUS protocol to transmit PAP packets or CHAP packets when the
device processes to relay.
For implementing identity authentication and network accessing, user should install the special
authentication client software, and spring the authentication flow to communicate with Radius
server through logging in authentication client. After 802.1x authentication is added in
web-based authentication mode, the user can download a special Java Applet program by
browser or other plug-in to replace 802.1x client.
For the environment which uses 802.1x authentication, installing client or downloading the
special Java Applet program become a mortal problem. To satisfy user’s actual requirement,
the manual describes an application scene based on web portal authentication. Web portal
authentication not only implements the basic device authentication without the client but also
implement the security detection to the terminal.
52.2 Web Portal Authentication Configuration Task List
1. Enable/disable web portal authentication globally (required)
2. Enable/disable web portal authentication of the port (required)
3. Configure the max. web portal binding number allowed by the port (optional)
4. Configure HTTP redirection address of web portal authentication (required)
5. Configure IP source address for communicating between accessing device and portal
server (required)
6. Enable dhcp snooping binding web portal function (optional)
7. Delete the binding information of web portal authentication
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1. Enable/disable web portal authentication globally
Command Explanation
Global Mode
webportal enable
no webportal enable
Enable/disable web portal authentication
globally.
2. Enable/disable web portal authentication of the port
Command Explanation
Port Mode
webportal enable
no webportal enable
Enable/disable web portal authentication of
the port.
3. Configure the max. web portal binding number allowed by the port
Command Explanation
Port Mode
webportal binding-limit <1-256>
no webportal binding-limit
Configure the max. web portal binding
number allowed by the port
4. Configure HTTP redirection address of web portal authentication
Command Explanation
Global Mode
webportal redirect <ip>
no webportal redirect
Configure HTTP redirection address of web
portal authentication.
5. Configure IP source address for communicating between accessing device and
portal server
Command Explanation
Global Mode
webportal nas-ip <ip-address>
no webportal nas-ip
Configure IP source address for
communicating between accessing device
and portal server.
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6. Enable dhcp snooping binding web portal function
Command Explanation
Port Mode
ip dhcp snooping binding webportal
no ip dhcp snooping binding webportal
Enable dhcp snooping binding web portal
function.
7. Delete the binding information of web portal authentication
Command Explanation
Admin Mode
clear webportal binding {mac WORD |
interface <ethernet IFNAME | IFNAME>
|}
Delete the binding information of web portal
authentication.
52-144
52.3 Web Portal Authentication Typical Example
Figure 52-1: Web portal typical application scene
In the above figure, pc1 is end-user, there is http browser in it, but no 802.1x authentication
client, pc1 wants to access the network through web portal authentication.
Switch1 is the accessing device, it configures accounting server’s address and port as
RADIUS server’s IP and port, and enable the accounting function. Ethernet 1/2 connects to
pc1, the port enables web portal authentication, and configure the redirection address and port
as portal server’s IP and port, so ethernet 1/2 forbids all flows except dhcp/dns/arp packets.
Switch2 is the aggregation switch. Ethernet1/2 connects to radius server while ethernet1/3
connects to portal server. The address of radius server is 192.168.40.100 while the address of
portal server is 192.168.40.99. Ethernet1/4 connects to DHCP server while ethernet1/5
connects to DNS server. Ethernet1/6 is trunk port and connects to ethernet1/4 of switch1.
The configuration of the common web portal authentication is as follows:
52-145
52-146
Switch(config)#interface vlan 1
Switch(config-if-vlan1)#ip address 192.168.40.50 255.255.255.0
Switch(config)#webportal enable
Switch(config)#webportal nas-ip 192.168.40.50
Switch(config)#webportal redirect 192.168.40.99
Switch(config)#interface ethernet 1/3
Switch(config-if-ethernet1/3)#webportal enable
Web portal authentication associates with DHCP snooping binding to use, the configuration is
as follows:
Switch(config)#ip dhcp snooping enable
Switch(config)#ip dhcp snooping binding enable
Switch(config)#interface ethernet 1/2
Switch(config-if-ethernet1/2)#webportal enable
Switch(config-if-ethernet1/2)#ip dhcp snooping binding webportal
52.4 Web Portal Authentication Troubleshooting
When using web portal authentication, the system will show the detailed prompt information if
the operation is wrong.
Web portal authentication is disabled by default. After ensure the configuration is correct, use
debug command and show command to check the relative information, if you can not
determine the cause of the problem, please send the recorded message to technical server
center of our company.
53-1
Chapter 53 VLAN-ACL Configuration
53.1 Introduction to VLAN-ACL
The user can configure ACL policy to VLAN to implement the accessing control of all ports in VLAN, and
VLAN-ACL enables the user to expediently manage the network. The user only needs to configure ACL policy
in VLAN, the corresponding ACL action can takes effect on all member ports of VLAN, but it does not need to
solely configure on each member port.
When VLAN ACL and Port ACL are configured at the same time, it will first match Port ACL due to Port ACL
priority is higher than VLAN-ACL.
VLAN-ACL ingress direction can implement the filtering of the packets, the packets match the specific rules
can be allowed or denied. ACL can support IP ACL, MAC ACL, MAC-IP ACL, IPv6 ACL. Ingress direction of
VLAN can bind four kinds of ACL at the same time.
53.2 VLAN-ACL Configuration Task List
1. Configure VLAN-ACL of IP type
2. Configure VLAN-ACL of MAC type
3. Configure VLAN-ACL of MAC-IP
4. Configure VLAN-ACL of IPv6 type
5. Show configuration and statistic information of VLAN-ACL
6. Clear statistic information of VLAN-ACL
1. Configure VLAN-ACL of IP type
Command Explanation
Global Mode
vacl ip access-group {<1-299> | WORD} {in
| out} [traffic-statistic] vlan WORD
no vacl ip access-group {<1-299> |
WORD} {in | out} vlan WORD
Configure or delete IP VLAN-ACL.
(Egress filtering is not supported by
switch.)
2. Configure VLAN-ACL of MAC type
Command Explanation
53-2
Global Mode
vacl mac access-group {<700-1199> |
WORD} {in | out} [traffic-statistic] vlan
WORD
no vacl mac access-group {<700-1199> |
WORD} {in | out} vlan WORD
Configure or delete MAC VLAN-ACL.
(Egress filtering is not supported by
switch.)
3. Configure VLAN-ACL of MAC-IP
Command Explanation
Global Mode
vacl mac-ip access-group {<3100-3299> |
WORD} {in | out} [traffic-statistic] vlan
WORD
no vacl mac-ip access-group
{<3100-3299> | WORD} {in | out} vlan
WORD
Configure or delete MAC-IP VLAN-ACL.
(Egress filtering is not supported by
switch.)
4. Configure VLAN-ACL of IPv6 type
Command Explanation
Global Mode
vacl ipv6 access-group (<500-699> |
WORD) {in | out} (traffic-statistic|) vlan
WORD
no ipv6 access-group {<500-699> | WORD}
{in | out} vlan WORD
Configure or delete IPv6 VLAN-ACL.
(Egress filtering is not supported by
switch).This switch only supports the
ipv6 standard acl.
5. Show configuration and statistic information of VLAN-ACL
Command Explanation
Admin Mode
show vacl [in | out] vlan [<vlan-id>]
Show the configuration and the statistic
information of VACL. (Egress filtering is
not supported by switch.)
6. Clear statistic information of VLAN-ACL
Command Explanation
53-3
Admin Mode
clear vacl [in | out] statistic vlan
[<vlan-id>]
Clear the statistic information of VACL.
(Egress filtering is not supported by
switch.)
53.3 VLAN-ACL Configuration Example
A company’s network configuration is shown below. All departments are divided by different VLANs.
Technique department is Vlan1 and finance department is Vlan2. It is required that technique department can
access the outside network at timeout, but finance department is not allowed to access the outside network at
any time for the sake of security. Then the following policies are configured:
Set the policy VACL_A for technique department. At timeout they can access the outside network, the
rule as permit, but other times the rule as deny, and the policy is applied to Vlan1.
Set the policy VACL_B of ACL for finance department. At any time they can not access the outside
network, but can access the inside network with no limitation, and apply the policy to Vlan2.
Network environment is shown as below:
Figure 53-1: VLAN-ACL configuration example
Configuration example:
1) First, configure a timerange, the valid time is the working hours of working day:
Switch(config)#time-range t1
Switch(config-time-range-t1)#periodic weekdays 9:00:00 to 12:00:00
53-4
Switch(config-time-range-t1)#periodic weekdays 13:00:00 to 18:00:00
2) Configure the extended acl_a of IP, at working hours; it only allows to access the resource within the
internal network (such as 192.168.0.255).
Switch(config)# ip access-list extended vacl_a
Switch(config-ip-ext-nacl-vacl_a)# permit ip any-source 192.168.0.0 0.0.0.255 time-range t1
Switch(config-ip-ext-nacl-vacl_a)# deny ip any-source any-destination time-range t1
3) Configure the extended acl_b of IP; at any time it only allows to access resource within the internal network
(such as 192.168.1.255).
Switch(config)#ip access-list extended vacl_b
Switch(config-ip-ext-nacl-vacl_a)# permit ip any-source 192.168.1.0 0.0.0.255
Switch(config-ip-ext-nacl-vacl_a)# deny ip any-source any-destination
4) Apply the configuration to VLAN
Switch(config)#firewall enable
Switch(config)#vacl ip access-group vacl_a in vlan 1
Switch(config)#vacl ip access-group vacl_b in vlan 2
53.4 VLAN-ACL Troubleshooting
When VLAN ACL and Port ACL are configured at the same time, the priority is port>VLAN if the two acl
are the same kind of ac, such as that they are all ip acl or they are all mac acl. So only the rules on port
is effective if the packets match the rule on port and vlan at the same time. Now, it will not meet the
principle of deny priority. If the two acl are not the same kine of acl, it can meet the principle of deny
priority.
Each ACL of different types can only apply one on a VLAN, such as the basic IP ACL, each VLAN can
applies one only.
54-5
Chapter 54 SAVI Configuration
54.1 Introduction to SAVI
SAVI (Source Address Validation Improvement) is a security authentication method that provides the
granularity level of the node source address. It gets the trusted node information (such as port, MAC address
information), namely, anchor information by monitoring the interaction process of the relative protocol packets
(such as ND protocol, DHCPv6 protocol) and using CPS (Control Packet Snooping) mechanism. After that, it
binds the anchor information with the node source address and sends the corresponding filter rules, allow the
packets which match the filter rules to pass only, so as to reach the aim that check the validity of node source
address.
SAVI function includes ND Snooping function, DHCPv6 Snooping function and RA Snooping according to the
protocol packet type. ND Snooping function is used to detect ND protocol packet, it sets IPv6 address binding
obtained by nodes with the stateless address configuration. DHCPv6 Snooping function is used to detect
DHCPv6 protocol packet, it sets IPv6 address binding obtained by nodes with the stateful address
configuration. RA Snooping function is used to avoid the lawless node sending the spurious RA packet.
54.2 SAVI Configuration
SAVI configuration task list:
1. Enable or disable SAVI function
2. Enable or disable application scene function for SAVI
3. Configure SAVI binding function
4. Configure the global max-dad-delay for SAVI
5. Configure the global max-dad-prepare-delay for SAVI
6. Configure the global max-slaac-life for SAVI
7. Configure the lifetime period for SAVI bind-protect
8. Enable or disable SAVI prefix check function
9. Configure IPv6 address prefix for a link
10. Configure the filter entry number of IPv6 address
11. Configure the check mode for SAVI conflict binding
12. Enable or disable user authentication
13. Enable or disable DHCPv6 trust of port
14. Enable or disable ND trust of port
15. Configure the binding number
54-6
1. Enable or disable SAVI function
Command Explanation
Global Mode
savi enable
no savi enable
Enable the global SAVI function, no
command disables the function.
2. Enable or disable application scene function for SAVI
Command Explanation
Global Mode
savi ipv6 {dhcp-only | slaac-only |
dhcp-slaac} enable
no savi ipv6 {dhcp-only | slaac-only |
dhcp-slaac} enable
Enable the application scene function for
SAVI, no command disables the function.
3. Configure SAVI binding function
Command Explanation
Global Mode
savi ipv6 check source binding ip
<ip-address> mac <mac-address>
interface <if-name> {type [slaac | dhcp]
lifetime <lifetime> | type static}
no savi ipv6 check source binding ip
<ip-address> interface <if-name>
Configure a static or dynamic binding
manually, no command deletes the
configured binding. This command may
be configured in a global function of savi
enable, slaac-only enable, dhcp-only
enable or dhcp-slaac enable.
4. Configure the global max-dad-delay for SAVI
Command Explanation
Global Mode
savi max-dad-delay <max-dad-delay>
no savi max-dad-delay
Configure the max. lifetime period of
SAVI binding at DETECTION state, no
command restores the default value.
5. Configure the global max-dad-prepare-delay for SAVI
Command Explanation
Global Mode
54-7
savi max-dad-prepare-delay
<max-dad-prepare-delay>
no savi max-dad-prepare-delay
Configure the max. redetection lifetime
period for SAVI binding, no command
restores the default value.
6. Configure the global max-slaac-life for SAVI
Command Explanation
Global Mode
savi max-slaac-life <max-slaac-life>
no savi max-slaac-life
Configure the lifetime period of the
dynamic slaac binding at BOUND state,
no command restores the default value.
7. Configure the lifetime period for SAVI bind-protect
Command Explanation
Global Mode
savi timeout bind-protect
<protect-time>
no savi timeout bind-protect
Configure the bind-protect lifetime period
to a port after its state from up to down,
no command restores the default value.
8. Enable or disable SAVI prefix check function
Command Explanation
Global Mode
ipv6 cps prefix check enable
no ipv6 cps prefix check enable
Enable the address prefix check for SAVI,
no command disables the function.
9. Configure IPv6 address prefix for a link
Command Explanation
Global Mode
ipv6 cps prefix <ip-address> vlan <vid>
no ipv6 cps prefix <ip-address>
Configure IPv6 address prefix for a link
manually, no command deletes the
configured address prefix.
10. Configure the filter entry number of IPv6 address
Command Explanation
Global Mode
54-8
savi ipv6 mac-binding-limit
<limit-num>
no savi ipv6 mac-binding-limit
Configure the corresponding dynamic
binding number for the same MAC
address, no command restores the
default value. Note: The binding number
only limits the dynamic binding, but does
not limit the static binding number.
11. Configure the check mode for SAVI conflict binding
Command Explanation
Global Mode
savi check binding <simple | probe>
mode
no savi check binding mode
Configure the check mode for the
conflict binding, no command deletes
the check mode.
12. Enable or disable user authentication
Command Explanation
Port Mode
savi ipv6 check source [ip-address
mac-address | ip-address |
mac-address]
no savi ipv6 check source
Enable the control authentication
function for user, no command disables
the function.
13. Enable or disable DHCPv6 trust of port
Command Explanation
Port Mode
ipv6 dhcp snooping trust
no ipv6 dhcp snooping trust
Enable DHCPv6 trusted port, no
command disables the trusted function.
(port is translated from trusted port into
untrusted port)
14. Enable or disable ND trust of port
Command Explanation
Port Mode
ipv6 nd snooping trust
no ipv6 nd snooping trust
Configure a port as slaac trust and RA
trust, no command deletes the port’s trust
54-9
function.
15. Configure the binding number
Command Explanation
Port Mode
savi ipv6 binding num <limit-num>
no savi ipv6 binding num
Configure the binding number of a port,
no command restores the default value.
Note: The binding number only limits the
dynamic binding, but does not limit the
static binding number.
54.3 SAVI Typical Application
In actual application, SAVI function is usually applied in access layer switch to check the validity of node
source address on direct-link. There are four typical application scenes for SAVI function: DHCP-Only,
Slaac-Only, DHCP-Slaac and Static binding. In network environment, users can select the corresponding
scene according to the actual requirement; in double stacks network, while SAVI function associates with IPv4
DHCP snooping to use, IPv4 and IPv6 source address authentication is implemented.
Typical network topology application for SAVI function:
54-10
Client_1 and Client_2 means two different user’s PC installed IPv6 protocol, respectively connect with port
Ethernet1/12 of Switch1 and port Ethernet1/13 of Switch2, and enable the source address check function of
SAVI. Ethernet1/1 and Ethernet1/2 are uplink ports of Switch1 and Switch2 respectively, enable DHCP trust
and ND trusted functions. Aggregation Switch3 enables DHCPv6 server function and route advertisement
function.
Configuration steps of SAVI DHCP-SLAAC scene:
Switch1>enable
Switch1#config
Switch1(config)#savi enable
Switch1(config)#savi ipv6 dhcp-slaac enable
Switch1(config)#savi check binding probe mode
Switch1(config)#interface ethernet1/1
Switch1(config-if-ethernet1/1)#ipv6 dhcp snooping trust
Switch1(config-if-ethernet1/1)#ipv6 nd snooping trust
Switch1(config-if-ethernet1/1)#exit
54-11
Switch1(config)#interface ethernet1/12-20
Switch1(config-if-port-range)#savi ipv6 check source ip-address mac-address
Switch1(config-if-port-range)#savi ipv6 binding num 4
Switch1(config-if-port-range)#exit
Switch1(config)#exit
Switch1#write
54.4 SAVI Troubleshooting
After ensure no problem about SAVI client hardware and cable, please check the status which may exist and
the propositional solutions in the following: If IPv6 packets are filtered incorrectly after enable SAVI function, please ensure the global SAVI function
enabled. After that, enable the global function of the corresponding SAVI scene according to the actual application scene and enable the port authentication function.
If client can not correctly obtain IPv6 address assigned by DHCPv6 server after enable SAVI function, please ensure DHCP port trust is configured by uplink port with DHCPv6 server.
If node binding can not be set for the new user after enable SAVI function, please check whether the
direct-link port configures the max. binding number, and whether the binding number reaches to the max. number. If the binding number exceeds the max. binding limit, it is recommended to configure the bigger binding limit.
If node binding can not be set for new user after configure the bigger binding limit, please check whether the direct-link port configures the corresponding binding number, and whether the corresponding binding number reaches to the max. number in the same MAC address. If the binding number exceeds
the max. binding limit, it is recommended to configure the bigger binding limit.
55-12
Chapter 55 MRPP Configuration
55.1 Introduction to MRPP
MRPP (Multi-layer Ring Protection Protocol), is a link layer protocol applied on Ethernet loop protection. It can
avoid broadcast storm caused by data loop on Ethernet ring, and restore communication among every node
on ring network when the Ethernet ring has a break link. MRPP is the expansion of EAPS (Ethernet link
automatic protection protocol).
MRPP protocol is similar to STP protocol on function, MRPP has below characters, compare to STP protocol:
<1> MRPP specifically uses to Ethernet ring topology
<2> fast convergence, less than 1 s. ideally it can reach 100-50 ms.
55.1.1 Conception Introduction
Figure 55-1: MRPP Sketch Map
1. Control VLAN
Control VLAN is a virtual VLAN, only used to identify MRPP protocol packet transferred in the link. To avoid
confusion with other configured VLAN, avoids configuring control VLAN ID to be the same with other
configured VLAN ID. The different MRPP ring should configure the different control VLAN ID.
2. Ethernet Ring (MRPP Ring)
Ring linked Ethernet network topology.
Each MRPP ring has two states.
Health state: The whole ring net work physical link is connected.
Break state: one or a few physical link break in ring network
SWITCH C
SWITCH A
Master E2Node
E1
Ring 1
SWITCH D
SWITCH B SWITCH F
SWITCH E SWITCH G
Ring 2
Master Node
E1E2
SWITCH H
55-13
3. nodes
Each switch is named after a node on Ethernet. The node has some types:
Primary node: each ring has a primary node, it is main node to detect and defend.
Transfer node: except for primary node, other nodes are transfer nodes on each ring.
The node role is determined by user configuration. As shown Figure 55-1, Switch A is primary node of Ring 1,
Switch B. Switch C; Switch D and Switch E are transfer nodes of Ring 1.
4. Primary port and secondary port
The primary node and transfer node have two ports connecting to Ethernet separately, one is primary port,
and another is secondary port. The role of port is determined by user configuration.
Primary port and secondary port of primary node.
The primary port of primary node is used to send ring health examine packet (hello), the secondary port is
used to receive Hello packet sending from primary node. When the Ethernet is in health state, the secondary
port of primary node blocks other data in logical and only MRPP packet can pass. When the Ethernet is in
break state, the secondary port of primary node releases block state, and forwards data packets.
There are no difference on function between Primary port and secondary port of transfer node.
The role of port is determined by user configuration. As shown in Figure 55-1, Switch A E1 is a primary port
while E2 is a secondary port.
5. Timer
The two timers are used when the primary node sends and receives MRPP protocol packet: Hello timer and
Fail Timer.
Hello timer: define timer of time interval of health examine packet sending by primary node primary port.
Fail timer: define timer of overtime interval of health examine packet receiving by primary node primary port.
The value of Fail timer must be more than or equal to the 3 times of value of Hello timer.
55.1.2 MRPP Protocol Packet Types
Packet Type Explanation
Hello packet (Health examine packet) Hello The primary port of primary node evokes to detect ring, if the
secondary port of primary node can receive Hello packet in
configured overtime, so the ring is normal.
LINK-DOWN (link Down event packet) After transfer node detects Down event on port, immediately
sends LINK-DOWN packet to primary node, and inform primary
node ring to fail.
LINK-DOWN-FLUSH_FDB packet After primary node detects ring failure or receives LINK-DOWN
packet, open blocked secondary port, and then uses two ports
55-14
55.1.3 MRPP Protocol Operation System
1. Link Down Alarm System
When transfer node finds themselves belonging to MRPP ring port Down, it sends link Down packet to
primary node immediately. The primary node receives link down packet and immediately releases block state
of secondary port, and sends LINK-DOWN-FLUSH-FDB packet to inform all of transfer nodes, refreshing own
MAC address forward list.
2. Poll System
The primary port of primary node sends Hello packet to its neighbors timely according to configured
Hello-timer.
If the ring is health, the secondary port of primary node receives health detect packet, and the primary node
keeps secondary port.
If the ring is break, the secondary port of primary node can’t receive health detect packet when timer is over
time. The primary releases the secondary port block state, and sends LINK-DOWN-FLUSH_FDB packet to
inform all of transfer nodes, to refresh own MAC address forward list.
3. Ring Restore
After the primary node occur ring fail, if the secondary port receives Hello packet sending from primary node,
the ring has been restored, at the same time the primary node block its secondary port, and sends its
neighbor LINK-UP-Flush-FDB packet.
After MRPP ring port refresh UP on transfer node, the primary node maybe find ring restore after a while. For
the normal data VLAN, the network maybe forms a temporary ring and creates broadcast storm. To avoid
temporary ring, transfer node finds it to connect to ring network port to refresh UP, immediately block
temporarily (only permit control VLAN packet pass), after only receiving LINK-UP-FLUSH-FDB packet from
primary node, and releases the port block state.
55.2 MRPP Configuration Task List
1) Globally enable MRPP
2) Configure MRPP ring
3) Configure the query time of MRPP
to send the packet, to inform each transfer node to refresh own
MAC address.
LINK-UP-FLUSH_FDB packet After primary detects ring failure to restore normal, and uses
packet from primary port, and informs each transfer node to
refresh own MAC address.
55-15
4) Configure the compatible mode
5) Display and debug MRPP relevant information
1) Globally enable MRPP
Command Explanation
Global Mode
mrpp enable
no mrpp enable Globally enable and disable MRPP.
2) Configure MRPP ring
Command Explanation
Global Mode
mrpp ring <ring-id>
no mrpp ring <ring-id>
Create MRPP ring. The “no” command
deletes MRPP ring and its configuration.
MRPP Ring Mode
control-vlan <vid>
no control-vlan
Configure control VLAN ID, format “no”
deletes configured control VLAN ID.
node-mode {master | transit} Configure node type of MRPP ring (primary
node or secondary node).
hello-timer < timer>
no hello-timer
Configure Hello packet timer sending from
primary node of MRPP ring, format “no”
restores default timer value.
fail-timer <timer>
no fail-timer
Configure Hello packet overtime timer
sending from primary node of MRPP ring,
format “no” restores default timer value.
enable
no enable
Enable MRPP ring, format “no” disables
enabled MRPP ring.
Port Mode
mrpp ring <ring-id> primary-port
no mrpp ring <ring-id> primary-port Specify primary port of MRPP ring.
mrpp ring <ring-id> secondary-port
no mrpp ring <ring-id> secondary-port Specify secondary port of MRPP ring.
55-16
3) Configure the query time of MRPP
Command Explanation
Global Mode
mrpp poll-time <20-2000> Configure the query interval of MRPP.
4) Configure the compatible mode
Command Explanation
Global Mode
mrpp errp compatible
no mrpp errp compatible
Enable the compatible mode for ERRP, the
no command disables the compatible
mode.
mrpp eaps compatible
no mrpp eaps compatible
Enable the compatible mode for EAPS, the
no command disables the compatible
mode.
errp domain <domain-id>
no errp domain <domain-id>
Create ERRP domain, the no command
deletes the configured ERRP domain.
5) Display and debug MRPP relevant information
Command Explanation
Admin Mode
debug mrpp
no debug mrpp
Disable MRPP module debug information,
format “no” disable MRPP debug
information output.
show mrpp {<ring-id>} Display MRPP ring configuration
information.
show mrpp statistics {<ring-id>} Display receiving data packet statistic
information of MRPP ring.
clear mrpp statistics {<ring-id>} Clear receiving data packet statistic
information of MRPP ring.
55-17
55.3 MRPP Typical Scenario
SWITCH A SWITCH B
E1 E2
Master Node E2 E1
MRPP Ring 4000
E1 E2E2 E1
SWITCH C SWITCH D
Figure 55-2: MRPP typical configuration scenario
The above topology often occurs on using MRPP protocol. The multi switch constitutes a single MRPP ring,
all of the switches only are configured an MRPP ring 4000, thereby constitutes a single MRPP ring.
In the above configuration, SWITCH A configuration is primary node of MRPP ring 4000, and configures E1/1
to primary port and E1/2 to secondary port. Other switches are secondary nodes of MRPP ring, configures
primary port and secondary port separately.
To avoid ring, it should temporarily disable one of the ports of primary node, when it enables each MRPP ring
in the whole MRPP ring; and after all of the nodes are configured, open the port.
When disable MRPP ring, it needs to insure the MRPP ring doesn’t have ring.
SWITCH A configuration Task Sequence:
Switch(Config)#mrpp enable
Switch(Config)#mrpp ring 4000
Switch(mrpp-ring-4000)#control-vlan 4000
Switch(mrpp-ring-4000)#fail-timer 18
Switch(mrpp-ring-4000)#hello-timer 5
Switch(mrpp-ring-4000)#node-mode master
Switch(mrpp-ring-4000)#enable
Switch(mrpp-ring-4000)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)#mrpp ring 4000 primary-port
Switch(config-If-Ethernet1/1)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)#mrpp ring 4000 secondary-port
Switch(config-If-Ethernet1/2)#exit
Switch(Config)#
55-18
SWITCH B configuration Task Sequence:
Switch(Config)#mrpp enable
Switch(Config)#mrpp ring 4000
Switch(mrpp-ring-4000)#control-vlan 4000
Switch(mrpp-ring-4000)#enable
Switch(mrpp-ring-4000)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)#mrpp ring 4000 primary-port
Switch(config-If-Ethernet1/1)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)#mrpp ring 4000 secondary-port
Switch(config-If-Ethernet1/2)#exit
Switch(Config)#
SWITCH C configuration Task Sequence:
Switch(Config)#mrpp enable
Switch(Config)#mrpp ring 4000
Switch(mrpp-ring-4000)#control-vlan 4000
Switch(mrpp-ring-4000)#enable
Switch(mrpp-ring-4000)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)#mrpp ring 4000 primary-port
Switch(config-If-Ethernet1/1)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)#mrpp ring 4000 secondary-port
Switch(config-If-Ethernet1/2)#exit
Switch(Config)#
SWITCH D configuration Task Sequence:
Switch(Config)#mrpp enable
Switch(Config)#mrpp ring 4000
Switch(mrpp-ring-4000)#control-vlan 4000
Switch(mrpp-ring-4000)#enable
Switch(mrpp-ring-4000)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)#mrpp ring 4000 primary-port
Switch(config-If-Ethernet1/1)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)#mrpp ring 4000 secondary-port
55-19
Switch(config-If-Ethernet1/2)#exit
Switch(Config)#
55.4 MRPP Troubleshooting
The normal operation of MRPP protocol depends on normal configuration of each switch on MRPP ring,
otherwise it is very possible to form ring and broadcast storm:
Configuring MRPP ring, you’d better disconnected the ring, and wait for each switch configuration, then
open the ring.
When the MRPP ring of enabled switch is disabled on MRPP ring, it ensures the ring of the MRPP ring
has been disconnected.
When there is broadcast storm on MRPP ring, it disconnects the ring firstly, and ensures if each switch
MRPP ring configuration on the ring is correct or not; if correct, restores the ring, and then observes the
ring is normal or not.
The convergence time of MRPP ring net is relative to the response mode of up/down. If use poll mode,
the convergence time as hundreds of milliseconds in simple ring net, if use interrupt mode, the
convergence time within 50 milliseconds.
Generally, the port is configured as poll mode, interrupt mode is only applied to better performance
environment, but the security of poll mode is better than interrupt mode, port-scan-mode {interrupt | poll}
command can be consulted.
In normal configuration, it still forms ring broadcast storm or ring block, please open debug function of
primary node MRPP, and used show MRPP statistics command to observe states of primary node and
transfer node and statistics information is normal or not, and then sends results to our Technology
Service Center.
56-20
Chapter 56 ULPP Configuration
56.1 Introduction to ULPP
Each ULPP group has two uplink ports, they are master port and slave port. The port may be a physical port
or a port channel. The member ports of ULPP group have three states: Forwarding, Standby, Down. Normally,
only one port at the forwarding state, the other port is blocked at the Standby state. When the master port has
the link problem, the master port becomes down state, and the slave port is switched to forwarding state.
Figure 56-1: the using scene of ULPP
The above figure uses the double-uplink network, this is the typical application scene of ULPP. SwitchA goes
up to SwitchD through SwitchB and SwitchC, port A1 and port A2 are the uplink ports. SwitchA configures
ULPP and port A1 is set as the master port and port A2 is set as the slave port. When port A1 in the
forwarding state has the problem, switch the uplink at once and port A2 turns into the forwarding state. After
this, when recovering the master port, if the preemption mode is not configured, port A2 keeps the Forwarding
state, port A1 turns into the Standby state.
After the preemption mode is enabled, so as to the master port preempts the slave port when it recovered
from the problem. For avoiding the frequent uplink switch caused by the abnormity problem, the preemption
delay mechanism is imported, and it needs to wait for some times before the master port preempt the slave
port. For keeping the continuance of the flows, the master port does not process to preempt by default, but
turns into the Standby state.
56-21
When configuring ULPP, it needs to specify the VLAN which is protected by this ULPP group through the
method of MSTP instances, and ULPP does not provide the protection to other VLANs.
When the uplink switch is happening, the primary forwarding entries of the device will not be applied to new
topology in the network. In the figure, SwitchA configures ULPP, the portA1 as the master port at forwarding
state, here the MAC address of PC is learned by Switch D from portD3. After this, portA1 has the problem, the
traffic is switched to portA2 to be forwarded. If there is the data sent to PC by SwitchD, still the data will be
forwarded from portD3, and will be lost. Therefore, when switching the uplink, the device of configuring ULPP
needs to send the flush packets through the port which is switched to Forwarding state, and update MAC
address tables and ARP tables of other devices in the network. ULPP respectively uses two kinds of flush
packets to update the entries: the updated packets of MAC address and the deleted packets of ARP.
For making use of the bandwidth resource enough, ULPP can implement VLAN load balance through the
configuration. As the picture illustrated, SwitchA configures two ULPP groups: portA1 is the master port and
portA2 is the slave port in group1, portA2 is the master port and portA1 is the slave port in group2, the VLANs
are protected by group1 and group2, they are 1-100 and 101-200. Here both portA1 and portA2 are in the
forwarding state; the master port and the slave port mutually back up, and respectively forward the packets of
the different VLAN ranges. When portA1 has the problem, the traffic of VLAN 1-200 are forwarded by portA2.
After this, when portA1 is recovering the normal state, portA2 forwards the data of VLAN 101-200 sequentially,
but the data of VLAN 1-100 is switched to portA1 to forward.
Figure 56-2: VLAN load balance
56-22
56.2 ULPP Configuration Task List
1. Create ULPP group globally
2. Configure ULPP group
3. Show and debug the relating information of ULPP
1. Create ULPP group globally
Command Explanation
Global Mode
ulpp group <integer>
no ulpp group <integer>
Configure and delete ULPP group
globally.
2. Configure ULPP group
Command Explanation
ULPP Group Mode
preemption mode
no preemption mode
Configure the preemption mode of
ULPP group. The no operation
deletes the preemption mode.
preemption delay <integer>
no preemption delay
Configure the preemption delay, the
no operation restores the default
value 30s.
control vlan <integer>
no control vlan
Configure the sending control VLAN,
no operation restores the default
value 1.
protect vlan-reference-instance
<instance-list>
no protect vlan-reference-instance
<instance-list>
Configure the protection VLANs, the
no operation deletes the protection
VLANs.
flush enable mac
flush disable mac
Enable or disable sending the flush
packets which update MAC address.
flush enable arp
flush disable arp
Enable or disable sending the flush
packets which delete ARP.
flush enable mac-vlan
flush disable mac-vlan
Enable or disable sending the flush
packets of deleting the dynamic
unicast mac according to vlan.
56-23
3. Show and debug the relating information of ULPP
Command Explanation
Admin Mode
show ulpp group [group-id] Show the configuration information of the
configured ULPP group.
show ulpp flush counter interface
{ethernet <IFNAME> | <IFNAME>}
Show the statistic information of the flush
packets.
show ulpp flush-receive-port Show flush type and control VLAN received
by the port.
clear ulpp flush counter interface
<name>
Clear the statistic information of the flush
packets.
debug ulpp flush {send | receive}
interface <name>
no debug ulpp flush {send | receive}
interface <name>
Show the information of the receiving and
sending flush packets, the no operation
disables the shown information.
debug ulpp flush content interface
<name>
no debug ulpp flush content interface
<name>
Show the contents of the received flush
packets, the no operation disables the
showing.
description <string>
no description
Configure or delete ULPP group
description.
Port Mode
ulpp control vlan <vlan-list>
no ulpp control vlan <vlan-list>
Configure the receiving control
VLANs, no operation restores the
default value 1.
ulpp flush enable mac
ulpp flush disable mac
Enable or disable receiving the flush
packets which update the MAC
address.
ulpp flush enable arp
ulpp flush disable arp
Enable or disable receiving the flush
packets which delete ARP.
ulpp flush enable mac-vlan
ulpp flush disable mac-vlan
Enable or disable receiving the flush
packets of mac-vlan type.
ulpp group <integer> master
no ulpp group <integer> master
Configure or delete the master port
of ULPP group.
ulpp group <integer> slave
no ulpp group <integer> slave
Configure or delete the slave port of
ULPP group.
56-24
debug ulpp error
no debug ulpp error
Show the error information of ULPP, the no
operation disables the showing.
debug ulpp event
no debug ulpp event
Show the event information of ULPP, the
no operation disables the showing.
56.3 ULPP Typical Examples
56.3.1 ULPP Typical Example1
Switch D
Switch B E1/1 E1/2 Switch C
E1/1 E1/2
Switch A
Figure 56-3: ULPP typical example1
The above topology is the typical application environment of ULPP protocol.
SwitchA has two uplinks, they are SwitchB and SwitchC. When any protocols are not enabled, this topology
forms a ring. For avoiding the loopback, SwitchA can configure ULPP protocol, the master port and the slave
port of ULPP group. When both master port and slave port are up, the slave port will be set as standby state
and will not forward the data packets. When the master port is down, the slave port will be set as forwarding
state and switch to the uplink. SwitchB and SwitchC can enable the command that receives the flush packets,
it is used to associate with ULPP protocol running of SwitchA to switch the uplink immediately and reduce the
switch delay.
When configuring ULPP protocol of SwitchA, first, create a ULPP group and configure the protection VLAN of
this group as vlan10, then configure interface Ethernet 1/1 as the master port, interface Ethernet 1/2 as the
slave port, the control VLAN as 10. SwitchB and SwitchC configure the flush packets that receive ULPP.
SwitchA configuration task list:
56-25
Switch(Config)#vlan 10
Switch(Config-vlan10)#switchport interface ethernet 1/1; 1/2
Switch(Config-vlan10)#exit
Switch(Config)#spanning-tree mst configuration
Switch(Config-Mstp-Region)#instance 1 vlan 10
Switch(Config-Mstp-Region)#exit
Switch(Config)#ulpp group 1
Switch(ulpp-group-1)#protect vlan-reference-instance 1
Switch(ulpp-group-1)#control vlan 10
Switch(ulpp-group-1)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)# ulpp group 1 master
Switch(config-If-Ethernet1/1)#exit
Switch(Config)#interface Ethernet 1/2
Switch(config-If-Ethernet1/2)# ulpp group 1 slave
Switch(config-If-Ethernet1/2)#exit
SwitchB configuration task list:
Switch(Config)#vlan 10
Switch(Config-vlan10)#switchport interface ethernet 1/1
Switch(Config-vlan10)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)# ulpp flush enable mac
Switch(config-If-Ethernet1/1)# ulpp flush enable arp
Switch(config-If-Ethernet1/1)# ulpp control vlan 10
SwitchC configuration task list:
Switch(Config)#vlan 10
Switch(Config-vlan10)#switchport interface ethernet 1/2
Switch(Config-vlan10)#exit
Switch(Config)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)# ulpp flush enable mac
Switch(config-If-Ethernet1/2)# ulpp flush enable arp
Switch(config-If-Ethernet1/2)# ulpp control vlan 10
56-26
56.3.2 ULPP Typical Example2
Switch D
Switch B E1/1 E1/2 Switch C
Figure 56-4: ULPP typical example2
ULPP can implement the VLAN-based load balance. As the picture illustrated, SwitchA configures two ULPP
groups: port E1/1 is the master port and port 1/2 is the slave port in group1, port 1/2 is the master port and
port 1/1 is the slave port in group2. The VLANs protected by group1 are 1-100 and by group2 are 101-200.
Here both port E1/1 and port E1/2 at the forwarding state, the master port and the slave port mutually backup,
respectively forward the packets of different VLAN ranges. When port E1/1 has the problem, the traffic of
VLAN 1-200 are forwarded by port E1/2. When port E1/1 is recovering the normal state, still port E1/2
forwards the data of VLAN 101-200, the data of VLAN 1-100 are switched to port E1/1 to forward.
SwitchA configuration task list:
Switch(Config)#spanning-tree mst configuration
Switch(Config-Mstp-Region)#instance 1 vlan 1-100
Switch(Config-Mstp-Region)#instance 2 vlan 101-200
Switch(Config-Mstp-Region)#exit
Switch(Config)#ulpp group 1
Switch(ulpp-group-1)#protect vlan-reference-instance 1
Switch(ulpp-group-1)#preemption mode
Switch(ulpp-group-1)#exit
Switch(Config)#ulpp group 2
Switch(ulpp-group-2)#protect vlan-reference-instance 2
Switch(ulpp-group-1)#preemption mode
Switch(ulpp-group-2)#exit
Switch(Config)#interface ethernet 1/1
Switch A
E1/2 E1/1 Vlan 1-100 Vlan 101-200
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Switch(config-If-Ethernet1/1)#switchport mode trunk
Switch(config-If-Ethernet1/1)#ulpp group 1 master
Switch(config-If-Ethernet1/1)#ulpp group 2 slave
Switch(config-If-Ethernet1/1)#exit
Switch(Config)#interface Ethernet 1/2
Switch(config-If-Ethernet1/2)#switchport mode trunk
Switch(config-If-Ethernet1/2)# ulpp group 1 slave
Switch(config-If-Ethernet1/2)# ulpp group 2 master
Switch(config-If-Ethernet1/2)#exit
SwitchB configuration task list:
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)#switchport mode trunk
Switch(config-If-Ethernet1/1)# ulpp flush enable mac
Switch(config-If-Ethernet1/1)# ulpp flush enable arp
SwitchC configuration task list:
Switch(Config)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)# switchport mode trunk
Switch(config-If-Ethernet1/2)# ulpp flush enable mac
Switch(config-If-Ethernet1/2)# ulpp flush enable arp
56.4 ULPP Troubleshooting
At present, configuration of more than 2 multi-uplinks is allowed, but it may cause loopback, so is not
recommended.
With the normal configuration, if the broadcast storm happen or the communication along the ring is
broken, please enable the debug of ULPP, copy the debug information of 3 minutes and the
configuration information, send them to our technical service center.
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Chapter 57 ULSM Configuration
57.1 Introduction to ULSM
ULSM (Uplink State Monitor) is used to process the port state synchronization. Each ULSM group is made up
of the uplink port and the downlink port, both the uplink port and the downlink port may be multiple. The port
may be a physical port or a port channel, but it can not be a member port of a port channel, and each port only
belongs to one ULSM group.
The uplink port is the monitored port of ULSM group. When all uplink ports are down or there is no uplink port
in ULSM group, ULSM group state is down. ULSM group state is up as long as one uplink port is up.
The downlink port is the controlled port, its state changes along with Up/Down of ULSM group and is always
the same with ULSM group state.
ULSM associates with ULPP to enable the downstream device to apperceive the link problem of the upstream
device and process correctly. As the picture illustrated, SwitchA configures ULPP, here the traffic is forwarded
by port A1. If the link between SwitchB and Switch D has the problem, SwitchA can not apperceive the
problem of the upstream link and sequentially forward the traffic from port A1, cause traffic losing.
Configuring ULSM on SwitchB can solve the above problems. The steps are: set port B5 as the uplink port of
ULSM group, port B6 as the downlink port. When the link between SwitchB and SwitchD has the problem,
both the downlink port B6 and the state of ULSM group are down. It causes Switch A on which ULPP is
configured to process uplink switchover and avoid the data dropped.
Figure 57-1: ULSM using scene
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57.2 ULSM Configuration Task List
1. Create ULSM group globally
2. Configure ULSM group
3. Show and debug the relating information of ULSM
1. Create ULSM group globally
Command explanation
Global Mode
ulsm group <group-id>
no ulsm group <group-id> Configure and delete ULSM group globally.
2. Configure ULSM group
Command explanation
Port Mode
ulsm group <group-id> {uplink |
downlink}
no ulsm group <group-id> {uplink |
downlink}
Configure the uplink/downlink port of
ULSM group, the no command deletes the
uplink/downlink port.
3. Show and debug the relating information of ULSM
Command Explanation
Admin Mode
show ulsm group [group-id] Show the configuration information of
ULSM group.
debug ulsm event
no debug ulsm event
Show the event information of ULSM, the
no operation disables the shown
information.
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57.3 ULSM Typical Example
Switch D
E1/3 E1/4
E1/2 Switch C Switch B E1/1
E1/1 E1/2
Switch A
Figure 57-2: ULSM typical example
The above topology is the typical application environment which is used by ULSM and ULPP protocol.
ULSM is used to process the port state synchronization, its independent running is useless, so it usually
associates with ULPP protocol to use. In the topology, SwitchA enables ULPP protocol, it is used to switch the
uplink. SwitchB and SwitchC enable ULSM protocol to monitor whether the uplink is down. If it is down, then
ULSM will execute the down operation for the downlink port to shutdown it, so ULPP protocol of Swtich A
executes the relative operation of the uplink switchover.
SwitchA configuration task list:
Switch(Config)#spanning-tree mst configuration
Switch(Config-Mstp-Region)#instance 1 vlan 1
Switch(Config-Mstp-Region)#exit
Switch(Config)#ulpp group 1
Switch(ulpp-group-1)#protect vlan-reference-instance 1
Switch(ulpp-group-1)#exit
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)# ulpp group 1 master
Switch(config-If-Ethernet1/1)#exit
Switch(Config)#interface Ethernet 1/2
Switch(config-If-Ethernet1/2)# ulpp group 1 slave
Switch(config-If-Ethernet1/2)#exit
SwitchB configuration task list:
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Switch(Config)#ulsm group 1
Switch(Config)#interface ethernet 1/1
Switch(config-If-Ethernet1/1)#ulsm group 1 downlink
Switch(config-If-Ethernet1/1)#exit
Switch(Config)#interface ethernet 1/3
Switch(config-If-Ethernet1/3)#ulsm group 1 uplink
Switch(config-If-Ethernet1/3)#exit
SwitchC configuration task list:
Switch(Config)#ulsm group 1
Switch(Config)#interface ethernet 1/2
Switch(config-If-Ethernet1/2)#ulsm group 1 downlink
Switch(config-If-Ethernet1/2)#exit
Switch(Config)#interface ethernet 1/4
Switch(config-If-Ethernet1/4)#ulsm group 1 uplink
Switch(config-If-Ethernet1/4)#exit
57.4 ULSM Troubleshooting
With the normal configuration, if the downlink port does not responds the down event of the uplink port,
please enable the debug function of ULSM, copy the debug information of 3 minutes and the
configuration information, and send them to our technical service center.
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Chapter 58 Mirror Configuration
58.1 Introduction to Mirror
Mirror functions include port mirror function, CPU mirror function, flow mirror function.
Port mirror refers to the duplication of data frames sent/received on a port to another port. The duplicated port
is referred to as mirror source port and the duplicating port is referred to as mirror destination port. A protocol
analyzer (such as Sniffer) or a RMON monitor will be connected at mirror destination port to monitor and
manage the network, and diagnose the problems in the network.
CPU mirror function means that the switch exactly copies the data frames received or sent by the CPU to a
port. Flow mirror function means that the switch exactly copies the data frames received by the specified rule
of a port to another port. The flow mirror will take effect only the specified rule is permit.
Switch supports one mirror destination port only. There is no limitation on mirror source ports, one port or
several ports is allowed. When there are more than one source ports, they can be in the same VLAN or in
different VLAN. The source port and destination port can be in different VLAN.
58.2 Mirror Configuration Task List
1. Specify mirror destination port
2. Specify mirror source port (CPU)
3. Specify flow mirror source
1. Specify mirror destination port
Command Explanation
Global Mode
monitor session <session> destination
interface <interface-number>
no monitor session <session> destination
interface <interface-number>
Specifies mirror destination port; the no
command deletes mirror destination source
port.
2. Specify mirror source port（CPU）
Command Explanation
Global Mode
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monitor session <session> source
{interface <interface-list> | cpu} {rx| tx|
both}
no monitor session <session> source
{interface <interface-list> | cpu}
Specifies mirror source port; the no command
deletes mirror source port.
3. Specify flow mirror source
Command Explanation
Global Mode
monitor session <session> source {interface
<interface-list>} access-group <num> {rx|tx|both}
no monitor session <session> source {interface
<interface-list>} access-group <num>
Specifies flow mirror source
port and apply rule; the no
command deletes flow mirror
source port.
58.3 Mirror Examples
1． Example:
The requirement of the configurations is shown as below: to monitor at interface 1 the data frames sent out by
interface 9 and received from interface 7, sent and received by CPU, and the data frames received by
interface 15 and matched by rule 120(The source IP address is 1.2.3.4 and the destination IP address is
5.6.7.8).
Configuration guidelines:
1. Configure interface 1 to be a mirror destination interface.
2. Configure the interface 7 ingress and interface 9 egress to be mirrored source.
3. Configure the CPU as one of the source.
4. Configure access list 120.
5. Configure access 120 to binding interface 15 ingress.
Configuration procedure is as follows:
Switch(config)#monitor session 1 destination interface ethernet 1/1
Switch(config)#monitor session 1 source interface ethernet 1/7 rx
Switch(config)#monitor session 1 source interface ethernet 1/9 tx
Switch(config)#monitor session 1 source cpu
Switch(config)#access-list 120 permit tcp 1.2.3.4 0.0.0.255 5.6.7.8 0.0.0.255
Switch(config)#monitor session 1 source interface ethernet 1/15 access-list 120 rx
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58.4 Device Mirror Troubleshooting
If problems occur on configuring port mirroring, please check the following first for causes:
Whether the mirror destination port is a member of a TRUNK group or not, if yes, modify the TRUNK
group.
If the throughput of mirror destination port is smaller than the total throughput of mirror source port(s),
the destination port will not be able to duplicate all source port traffic; please decrease the number of
source ports, duplicate traffic for one direction only or choose a port with greater throughput as the
destination port. Mirror destination port can not be pulled into Isolate vlan, or will affect mirror between
VLAN.
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Chapter 59 sFlow Configuration
59.1 Introduction to sFlow
The sFlow (RFC 3176) is a protocol based on standard network export and used on monitoring the network
traffic information developed by the InMon Company. The monitored switch or router sends date to the client
analyzer through its main operations such as sampling and statistic, then the analyzer will analyze according
to the user requirements so to monitor the network.
A sFlow monitor system includes: sFlow proxy, central data collector and sFlow analyzer. The sFlow proxy
collects data from the switch using sampling technology. The sFlow collector is for formatting the sample data
statistic which is to be forwarded to the sFlow analyzer which will analyze the sample data and perform
corresponding measure according to the result. Our switch here acts as the proxy and central data collector in
the sFlow system. We have achieved data sampling and statistic targeting physical port.
Our data sample includes the IPv4 and IPv6 packets. Extensions of other types are not supported so far. As
for non IPv4 and IPv6 packet, the unify HEADER mode will be adopted following the requirements in
RFC3176, copying the head information of the packet based on analyzing the type of its protocol.
The latest sFlow protocol presented by InMon Company is the version 5. Since it is the version 4 which is
realized in the RFC3176, version conflict might exist in some case such as the structure and the packet format.
This is because the version 5 has not become the official protocol, so, in order to be compatible with current
applications, we will continue to follow the RFC3176.
59.2 sFlow Configuration Task List
1. Configure sFlow Collector address
Command Explanation
Global and Port Mode
sflow destination <collector-address>
[<collector-port>]
no sflow destination
Configure the IP address and port number of
the host in which the sFlow analysis software
is installed. As for the ports, if IP address is
configured on the port, the port configuration
will be applied, or else will be applied the
global configuration. The “no sflow
destination” command restores to the default
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port value and deletes the IP address.
2. Configure the sFlow proxy address
Command Explanation
Global Mode
sflow agent-address <collector-address>
no sflow agent-address
Configure the source IP address applied by
the sFlow proxy; the “no” form of the
command deletes this address.
3. Configure the sFlow proxy priority
Command Explanation
Global Mode
sflow priority <priority-value>
no sflow priority
Configure the priority when sFlow receives
packet from the hardware; the “no sflow
priority” command restores to the default
4. Configure the packet head length copied by sFlow
Command Explanation
Port Mode
sflow header-len <length-value>
no sflow header-len
Configure the length of the packet data head
copied in the sFlow data sampling; the “no”
form of this command restores to the default
value.
5. Configure the max. data head length of the sFlow packet
Command Explanation
Port Mode
sflow data-len <length-value>
no sflow data-len
Configure the max. length of the data packet
in sFlow; the “no” form of this command
restores to the default.
6. Configure the sampling rate value
Command Explanation
Port Mode
sflow rate {input <input-rate> | output
<output-rate >}
Configure the sampling rate when sFlow
performing hardware sampling. The “no”
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no sflow rate [input | output] command deletes the rate value.
7. Configure the sFlow statistic sampling interval
Command Explanation
Port Mode
sflow counter-interval <interval-value>
no sflow counter-interval
Configure the max. interval when sFlow
performing statistic sampling. The “no” form of
this command deletes
8. Configure the analyzer used by sFlow
Command Explanation
Global Mode
sflow analyzer sflowtrend
no sflow analyzer sflowtrend
Configure the analyzer used by sFlow, the no
command deletes the analyzer.
59.3 sFlow Examples
SWITCH PC
Figure 59-1: sFlow configuration topology
As shown in the figure, sFlow sampling is enabled on the port 1/1 and 1/2 of the switch. Assume the sFlow
analysis software is installed on the PC with the address of 192.168.1.200. The address of the layer 3
interface on the SwitchA connected with PC is 192.168.1.100. A loopback interface with the address of
10.1.144.2 is configured on the SwitchA. sFlow configuration is as follows:
Configuration procedure is as follows:
Switch#config
Switch (config)#sflow aging-address 10.1.144.2
Switch (config)#sflow destination 192.168.1.200
Switch (config)#sflow priority 1
Switch (config)# interface ethernet1/1
Switch (Config-If-Ethernet1/1)#sflow rate input 10000
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Switch (Config-If-Ethernet1/1)#sflow rate output 10000
Switch (Config-If-Ethernet1/1)#sflow counter-interval 20
Switch (Config-If-Ethernet1/1)#exit
Switch (config)# interface ethernet1/2
Switch (Config-If-Ethernet1/2)#sflow rate input 20000
Switch (Config-If-Ethernet1/2)#sflow rate output 20000
Switch (Config-If-Ethernet1/2)#sflow counter-interval 40
59.4 sFlow Troubleshooting
In configuring and using sFlow, the sFlow server may fail to run properly due to physical connection failure,
wrong configuration, etc. The user should ensure the following:
Ensure the physical connection is correct
Guarantee the address of the sFlow analyzer configured under global or port mode is accessible.
If traffic sampling is required, the sampling rate of the interface must be configured
If statistic sampling is required, the statistic sampling interval of the interface must be configured
If the examination remains unsolved, please contact with the technical service center of our
company.
60-39
Chapter 60 RSPAN Configuration
60.1 Introduction to RSPAN
Port mirroring refers to the duplication of data frames sent/received on a port to another port. The duplicated
port is referred to as mirror source port and the duplicating port is referred to as mirror destination port. It is
more convenience for network administrator to monitor and manage the network and diagnostic after the
mirroring function achieved. But it only used for such instance that the mirror source port and the mirror
destination ports are located in the same switch.
RSPAN (remote switched port analyzer) refers to remote port mirroring. It eliminates the limitation that the
source port and the destination port must be located on the same switch. This feature makes it possible for
the source port and the destination port to be located on different devices in the network, and facilitates the
network administrator to manage remote switches. It can’t forward traffic flows on remote mirror VLAN.
There are three types of switches with the RSPAN enabled:
1. Source switch: The switch to which the monitored port belongs. The source switch copies the mirrored
traffic flows to the Remote VLAN, and then through Layer 2 forwarding, the mirrored flows are sent to
an intermediate switch or destination switch.
2. Intermediate switch: Switches between the source switch and destination switch on the network.
Intermediate switch forwards mirrored flows to the next intermediate switch or the destination switch.
Circumstances can occur where no intermediate switch is present, if a direct connection exists
between the source and destination switches.
3. Destination switch: The switch to which the destination port for remote mirroring belongs. It forwards
mirrored flows it received from the Remote VLAN to the monitoring device through the destination
port.
When configuring the RSPAN mirroring of the source switch, reflector port mode or destination mirror port
mode can be selected. The destination switch will redirect all the data frames in the RSPAN VLAN to the
RSPAN destination port. For RSPAN mirroring, normal mode and advanced mode can be chosen, normal is
introduced by default and fit the normal user. The advanced mode fit the advanced user.
1. Advanced mode: To redirect data frames in RSPAN VLAN to the RSPAN destination port, the
intermediary and destination devices should support the redirection of flow.
2. Normal mode: To configure the RSPAN destination port in the RSPAN VLAN. Thus, datagrams in the
RSPAN VLAN will be broadcasted to the destination port. In this mode, the destination port should be
in RSPAN VLAN, and the source port should not be configured for broadcasting storm control.
TRUNK ports should be configured carefully in order not to forward RSPAN datagrams to external
networks. The normal mode has the benefit of easy configuration, and reduced system resources.
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To be noticed: Normal mode is introduced by default. When using the normal mode, datagrams with reserved
MAC addresses cannot be broadcasted.
For chassis switches, at most 4 mirror destination ports are supported, and source or destination port of one
mirror session can be configured on each line card. For box switches, only one mirror session can be
configured. The number of the source mirror ports is not limited, and can be one or more. Multiple source
ports are not restricted to be in the same VLAN. The destination port and the source ports can be in different
VLAN.
For configuration of RSPAN, a dedicated RSPAN VLAN should be configured first for carrying the RSPAN
datagrams. The default VLAN, dynamic VLAN, private VLAN, multicast VLAN, and the layer 3 interface
enabled VLAN cannot be configured as the RSPAN VLAN. The reflector port must belong to the RSPAN
VLAN. The destination port should be connected to the Monitor and the configured as access port or the
TRUNK port. The RSPAN reflector port will be working dedicatedly for mirroring, when a port is configured as
a reflector port, it will discards all the existing connections to the remote peer, disable configurations related to
loopback interfaces, and stop forwarding datagram. Connectivity between the source and destination switch
for Remote VLAN, should be made sure by configuration.
To be noticed:
1. Layer 3 interfaces related to RSPAN VLAN should not be configured on the source, intermediate, and
the destination switches, or the mirrored datagrams may be discarded.
2. For the source and intermediate switches in the RSPAN connections, the native VLAN of TRUNK port
cannot be configured as the RSPAN VLAN, Otherwise the RSPAN tag will be disposed before reaching
the destination switches.
3. The source port, in access or trunk mode, should not be added to RSPAN VLAN if advanced RSPAN
mode is chosen. When the reflector port is used for a inter-card mirroring of CPU TX data, it must be
configured as TRUNK port and allows the RSPAN VLAN data passing, the Native VLAN should not be
configured as RSPAN VLAN.
4. When configuring the remote mirroring function, the network bandwidth should be considered in order
to carry the network flow and the mirrored flow.
Keywords:
RSPAN: Remote Switched Port Analyzer.
RSPAN VLAN: Dedicated VLAN for RSPAN.
RSPAN Tag: The VLAN tag which is attached to MTP of the RSPAN datagrams.
Reflector Port: The local mirroring port between the RSPAN source and destination ports, which is not
directly connected to the intermediate switches.
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60.2 RSPAN Configuration Task List
1. Configure RSPAN VLAN
2. Configure mirror source port（cpu）
3. Configure mirror destination port
4. Configure reflector port
5. Configure remote VLAN of mirror group
1. Configure RSPAN VLAN
Command Explanation
VLAN Mode
remote-span
no remote-span
To configure the specified VLAN as RSPAN
VLAN. The no command will remove the
configuration of RSPAN VLAN.
2. Configure mirror source port(CPU)
Command Explanation
Global Mode
monitor session <session> source
{interface <interface-list> | cpu [slot
<slotnum>]} {rx| tx| both}
no monitor session <session> source
{interface <interface-list> | cpu [slot
<slotnum>]}
To configure mirror source port; The no
command deletes the mirror source port.
3. Configure mirror destination port
Command Explanation
Global Mode
monitor session <session> destination
interface <interface-number>
no monitor session <session>
destination interface <interface-number>
To configure mirror destination interface; The
no command deletes the mirror destination
port.
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4. Configure reflector port
Command Explanation
Global Mode
monitor session <session> reflector-port
<interface-number>
no monitor session <session>
reflector-port
To configure the interface to reflector
port; The no command deletes the reflector
port.
5. Configure remote VLAN of mirror group
Command Explanation
Global Mode
monitor session <session>
remote vlan <vid>
no monitor session <session> remote
vlan
To configure remote VLAN of mirror
group, the no command deletes the remote
VLAN of mirror group.
60.3 Typical Examples of RSPAN
Before RSPAN is invented, network administrators had to connect their PCs directly to the switches, in order
to check the statistics of the network.
However, with the help of RSPAN, the network administrators can configure and supervise the switches
remotely, which brings more efficiency. The figure below shows a sample application of RSPAN.
Destination Switch Source Switch Intermediate Switch
E9
E2 E7 E1 E6 E10
PC1 Monitor
Figure 60-1: RSPAN Application Sample
60-43
Two configuration solutions can be chosen for RSPAN: the first is without reflector port, and the other is with
reflector port. For the first one, only one fixed port can be connected to the intermediate switch. However, no
reflector port has to be configured. This maximizes the usage of witch ports. For the latter one, the port
connected to the intermediate switch is not fixed. Datagrams can be broadcasted in the RSPAN VLAN
through the loopback, which is much more flexible.
The normal mode configuration is show as below:
Solution 1:
Source switch:
Interface ethernet 1/1 is the source port for mirroring.
Interface ethernet 1/2 is the destination port which is connected to the intermediate switch.
RSPAN VLAN is 5.
Switch(config)#vlan 5
Switch(Config-Vlan5)#remote-span
Switch(Config-Vlan5)#exit
Switch(config)#interface ethernet 1/2
Switch(Config-If-Ethernet1/2)#switchport mode trunk
Switch(Config-If-Ethernet1/2)#exit
Switch(config)#monitor session 1 source interface ethernet1/1 rx
Switch(config)#monitor session 1 destination interface ethernet1/2
Switch(config)#monitor session 1 remote vlan 5
Intermediate switch:
Interface ethernet1/6 is the source port which is connected to the source switch.
Interface ethernet1/7 is the destination port which is connected to the intermediate switch. The native VLAN of
this port cannot be configured as RSPAN VLAN, or the mirrored data may not be carried by the destination
switch.
RSPAN VLAN is 5.
Switch(config)#vlan 5
Switch(Config-Vlan5)#remote-span
Switch(Config-Vlan5)#exit
Switch(config)#interface ethernet 1/6-7
Switch(Config-If-Port-Range)#switchport mode trunk
Switch(Config-If-Port-Range)#exit
Destination switch:
Interface ethernet1/9 is the source port, which is connected to the source switch.
Interface ethernet1/10 is the destination port which is connected to the monitor. This port is required to be
configured as an access port, and belong to the RSPAN VLAN.
RSPAN VLAN is 5.
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Switch(config)#vlan 5
Switch(Config-Vlan5)#remote-span
Switch(Config-Vlan5)#exit
Switch(config)#interface ethernet 1/9
Switch(Config-If-Ethernet1/9)#switchport mode trunk
Switch(Config-If-Ethernet1/9)#exit
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#switchport access vlan 5
Switch(Config-If-Ethernet1/10)#exit
Solution 2:
Source switch:
Interface ethernet 1/1 is the source port.
Interface ethernet 1/2 is the TRUNK port, which is connected to the intermediate switch. The native VLAN
should not be a RSPAN VLAN.
Interface Ethernet 1/3 is a reflector port. The reflector port belongs to the RSPAN VLAN; it is access port or
TRUNK port of the RSPAN VLAN.
RSPAN VLAN is 5.
Switch(config)#vlan 5
Switch(Config-Vlan5)#remote-span
Switch(Config-Vlan5)#exit
Switch(config)#interface ethernet1/2
Switch(Config-If-Ethernet1/2)#switchport mode trunk
Switch(Config-If-Ethernet1/2)#exit
Switch(config)#interface ethernet 1/3
Switch(Config-If-Ethernet1/3)#switchport mode trunk
Switch(Config-If-Ethernet1/3)#exit
Switch(config)#monitor session 1 source interface ethernet1/1 rx
Switch(config)#monitor session 1 reflector-port ethernet1/3
Switch(config)#monitor session 1 remote vlan 5
Intermediate switch:
Interface ethernet1/6 is the source port which is connected to the source switch.
Interface ethernet1/7 is the destination port which is connected to the destination switch. The native VLAN of
the port should not be configured as RSPAN VLAN, or the mirrored data may not be carried by the destination
switch.
RSPAN VLAN is 5.
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Switch(config)#vlan 5
Switch(Config-Vlan5)#remote-span
Switch(Config-Vlan5)#exit
Switch(config)#interface ethernet 1/6-7
Switch(Config-If-Port-Range)#switchport mode trunk
Switch(Config-If-Port-Range)#exit
Destination switch:
Interface ethernet1/9 is the source port which is connected to the source switch.
Interface ethernet1/10 is the destination port which is connected to the monitor. This port is required to be
configured as an access port, and belong to the RSPAN VLAN.
RSPAN VLAN is 5.
Switch(config)#vlan 5
Switch(Config-Vlan5)#remote-span
Switch(Config-Vlan5)#exit
Switch(config)#interface ethernet 1/9
Switch(Config-If-Ethernet1/9)#switchport mode trunk
Switch(Config-If-Ethernet1/9)#exit
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#switchport access vlan 5
Switch(Config-If-Ethernet1/10)#exit
60.4 RSPAN Troubleshooting
Due to the following reasons, RSPAN may not function:
Whether the destination mirror port is a member of the Port-channel group. If so, please change the
Port-channel group configuration;
The throughput the destination port is less than the total throughput of the source mirror ports. If so, the
destination cannot catch all the datagrams from every source ports. To solve the problem, please reduce
the number of the source ports, or mirror only single direction data flow, or choose some other port with
higher capacity as the destination port.
Between the source switch and the intermediate switch, whether the native VLAN of the TRUNK ports is
configured as RSPAN VLAN. If so, please change the native VLAN for the TRUNK ports.
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Chapter 61 ERSPAN
61.1 Introduction to ERSPAN
ERSPAN（Encapsulated Remote Switched Port Analyzer）eliminates the limitation that the source port and the
destination port must be located on the same switch. This feature makes it possible for the source port and
the destination port to be located on different devices in the network, and facilitates the network administrator
to manage remote switches. Compared with the traditional RSPAN, ERSPAN configuration is simpler and it
makes the monitored traffic to be transmitted in the specified tunnel.
To be noticed 1. Monitor source of ERSPAN monitor only supports port monitor, it does not support CPU monitor and
flow monitor presently. 2. For the source and destination switches in the ERSPAN connections, a tunnel must be existed. 3. When configuring the remote mirror function, the network bandwidth should be considered in order
to carry the network flow and the mirrored flow.
Keywords:
ERSPAN: Encapsulated Remote Switched Port Analyzer.
61.2 ERSPAN Configuration Task List
1. Specify mirror source port
Command Explanation
Global Mode
monitor session <session> source
{interface <interface-list>} {rx| tx| both}
no monitor session <session> source
{interface <interface-list>}
Specify the mirror source port; the no
command deletes the mirror source port.
2. Specify mirror destination tunnel
Command Explanation
Global Mode
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monitor session <session> destination
tunnel <tunnel-number>
no monitor session <session>
destination tunnel <tunnel-number>
Specify the mirror destination tunnel; the no
command deletes the mirror destination
tunnel.
3. Appoint the mirror destination, and the destination can be the physical port or the tunnel
Command Explanation
Global Mode
monitor session <session> destination tunnel
interface <interface-number> desmac < MAC
address > desIP < Dest IP address > scrIP < Source
IP address
no monitor session <session> destination tunnel
interface <interface-number>
Appoint the mirror destination
to be the physical port or the
tunnel; the no command
deletes the mirror destination.
61.3 Typical Examples of ERSPAN
Before ERSPAN is invented, network administrators had to connect their PCs directly to the switches, in order
to check the status of the network.
However, with the help of ERSPAN, network administrators can configure and supervise the switches
remotely, which brings more efficiency.
In Layer 3 network, Device A connects to the marketing department through Ethernet 1/1, and connects to
Ethernet1/2 of Device B through Ethernet 1/2; Device C connects to the server through Ethernet 1/2, and
connects to Ethernet 1/1 of Device B through Ethernet 1/1. Server is able to monitor the bidirectional traffic of
the marketing department across a GRE tunnel by configuring remote port mirroring. The figure below shows
a sample application of ERSPAN.
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Figure 61-1: ERSPAN application diagram
Before configuring layer-3 remote port mirroring, make sure that you have created a GRE tunnel that
connects the source and destination device, and ensure the normal transmitting for GRE tunnel.
The configuration of Layer 3 remote port mirror needs to be processed on the source and destination devices,
respectively. Both the source and destination ports are configured on the source and destination devices and
their differences are as follows:
1) On Device A, configure the port which you want to monitor as the source port and configure the tunnel
interface as the destination port.
2) On Device C, configure the physical port corresponding to the tunnel interface as the source port and
configure the port that connects the data monitor device as the destination port.
(1) Configure IP addresses
Configure IP address and subnet mask for the interfaces, configuration procedures is omitted.
(2) Configure Device A (the source device)
# Create interface Tunnel1, and configure an IP address and mask for it.
SwitchA(config)#interface tunnel 1
SwitchA(config-if-tunnel1)# tunnel mode gre ip
SwitchA (config-if-tunnel1)#ip address 50.1.1.1 255.255.255.0
# Configure Tunnel1 to operate in GRE tunnel mode, and configure source and destination IP addresses for it.
SwitchA(config-if-tunnel1)# tunnel source 10.1.1.1
SwitchA(config-if-tunnel1)# tunnel destination 40.1.1.1
SwitchA(config-if-tunnel1)# exit
# Configure OSPF protocol.
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SwitchA (config)#router ospf
SwitchA (config-router)#network 0.0.0.0/0 area 0
SwitchA (config-router)#exit
# Configure Ethernet 1/1 as a source port and Tunnel1 as the destination port of local mirroring group 1.
SwitchA(config)#monitor session 4 destination tunnel 1
SwitchA(config)#monitor session 4 source interface ethernet 1/1 both
(3) Configure Device B (the intermediate device)
# Configure OSPF protocol.
SwitchB (config)#router ospf
SwitchB (config-router)#network 0.0.0.0/0 area 0
SwitchB (config-router)#exit
(4) Configure Device C (the destination device)
# Create interface Tunne1, and configure an IP address and mask for it.
SwitchC(config)#interface tunnel 1
SwitchC (config-if-tunnel1)# tunnel mode gre ip
SwitchC (config-if-tunnel1)#ip address 50.1.1.2 255.255.255.0
# Configure Tunnel1 to operate in GRE tunnel mode, and configure source and destination IP addresses for it.
SwitchC (config-if-tunnel1)# tunnel source 40.1.1.1
SwitchC (config-if-tunnel1)# tunnel destination 10.1.1.1
SwitchC (config-if-tunnel1)# exit
# Configure OSPF protocol.
SwitchC (config)#router ospf
SwitchC (config-router)#network 0.0.0.0/0 area 0
SwitchC (config-router)#exit
# Configure Ethernet 1/1 as a source port and Ethernet 1/2 as the destination port of local mirroring group 1.
SwitchC (config)#monitor session 1 destination interface ethernet 1/2
SwitchC (config)#monitor session 1 source interface ethernet 1/1 rx
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61.4 ERSPAN Troubleshooting
If problems occur when configuring ERSPAN, please check whether the problem is caused by the following
reasons:
Make sure GRE tunnel configuration to ensure the normal transmission for the traffic.
If the throughput of mirror destination port is smaller than the total throughput of mirror source port(s),
the destination port will not be able to duplicate the traffic of all source port; please decrease the number
of source ports, duplicate traffic for one direction only or choose a port with greater throughput as the
destination port.
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Chapter 62 SNTP Configuration
62.1 Introduction to SNTP
The Network Time Protocol (NTP) is widely used for clock synchronization for global computers connected to
the Internet. NTP can assess packet sending/receiving delay in the network, and estimate the computer’s
clock deviation independently, so as to achieve high accuracy in network computer clocking. In most positions,
NTP can provide accuracy from 1 to 50ms according to the characteristics of the synchronization source and
network route.
Simple Network Time Protocol (SNTP) is the simplified version of NTP, removing the complex algorithm of
NTP. SNTP is used for hosts who do not require full NTP functions; it is a subset of NTP. It is common practice
to synchronize the clocks of several hosts in local area network with other NTP hosts through the Internet, and
use those hosts to provide time synchronization service for other clients in LAN. The figure below depicts a
NTP/SNTP application network topology, where SNTP mainly works between second level servers and
various terminals since such scenarios do not require very high time accuracy, and the accuracy of SNTP (1
to 50 ms) is usually sufficient for those services.
Figure 62-1: Working Scenario
Switch implements SNTPv4 and supports SNTP client unicast as described in RFC2030; SNTP client
multicast and unicast are not supported, nor is the SNTP server function.
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62.2 Typical Examples of SNTP Configuration
Figure 62-2: Typical SNTP Configuration
All switches in the autonomous zone are required to perform time synchronization, which is done through two
redundant SNTP/NTP servers. For time to be synchronized, the network must be properly configured. There
should be reachable route between any switch and the two SNTP/NTP servers.
For example, assume the IP addresses of the SNTP/NTP servers are 10.1.1.1 and 20.1.1.1, respectively,
and SNTP/NTP server function (such as NTP master) is enabled, then configurations for any switch should
like the following:
Switch#config
Switch(config)#sntp server 10.1.1.1
SNTP/NTP SNTP/NTP SERVER SERVER
… …
SWITCH SWITCH SWITCH
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Chapter 63 NTP Function Configuration
63.1 Introduction to NTP Function
The NTP (Network Time Protocol) synchronizes timekeeping spans WAN and LAN among distributed time
servers and clients, it can get millisecond precision. The introduction of event, state, transmit function and
action are defined in RFC-1305.
The purpose of using NTP is to keep consistent timekeeping among all clock-dependent devices within the
network so that the devices can provide diverse applications based on the consistent time.
For a local system running NTP, its time can be synchronized by other reference sources and can be used as
a reference source to synchronize other clocks, also can synchronize each other by transmit NTP packets.
63.2 NTP Function Configuration Task List
1. To enable NTP function
2. To configure NTP server function
3. To configure the max. number of broadcast or multicast servers supported by the NTP client
4. To configure time zone
5. To configure NTP access control list
6. To configure NTP authentication
7. To specified some interface as NTP broadcast/multicast client interface
8. To configure some interface can’t receive NTP packets
9. Display information
10. Debug
1. To enable NTP function
Command Explication
Global Mode
ntp enable
ntp disable To enable or disable NTP function.
2. To configure NTP server function
Command Explication
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Global Mode
ntp server {<ip-address> |
<ipv6-address>} [version <version_no>]
[key <key-id>]
no ntp server {<ip-address> |
<ipv6-address>}
To enable the specified time server of time
source.
3. To configure the max. number of broadcast or multicast servers supported by the NTP client
Command Explication
Global Mode
ntp broadcast server count <number>
no ntp broadcast server count
Set the max. number of broadcast or
multicast servers supported by the NTP
client. The no operation will cancel the
configuration and restore the default value.
4. To configure time zone
Command Explication
Global Mode
clock timezone WORD {add | subtract}
<0-23> [<0-59>]
no clock timezone WORD
This command configures timezone in
global mode, the no command deletes the
configured timezone.
5. To configure NTP access control list
Command Explication
Global Mode
ntp access-group server <acl>
no ntp access-group server < acl> To configure NTP server access control list.
6. To configure NTP authentication
Command Explication
Global Mode
ntp authenticate
no ntp authenticate To enable NTP authentication function.
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ntp authentication-key <key-id> md5
<value>
no ntp authentication-key <key-id>
To configure authentication key for NTP
authentication.
ntp trusted-key <key-id>
no ntp trusted-key <key-id> To configure trusted key.
7. To specified some interface as NTP multicast client interface
Command Explication
Vlan Mode
ntp multicast client
no ntp multicast client
To configure specified interface to receive
NTP multicast packets.
ntp ipv6 multicast client
no ntp ipv6 multicast client
To configure specified interface to receive
IPv6 NTP multicast packets.
8. To configure some interface can’t receive NTP packets
Command Explication
Vlan Mode
ntp disable
no ntp disable To disable the NTP function.
9. Display information
Command Explication
Admin Mode
show ntp status To display the state of time synchronize.
show ntp session [ <ip-address> |
<ipv6-address> ] To display the information of NTP session.
10. Debug
Command Explication
Admin Mode
debug ntp authentication
no debug ntp authentication
To enable debug switch of NTP
authentication.
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debug ntp packets [send | receive]
no debug ntp packets [send | receive]
To enable debug switch of NTP packet
information.
debug ntp adjust
no debug ntp adjust
To enable debug switch of time update
information.
debug ntp sync
no debug ntp sync
To enable debug switch of time
synchronize information.
debug ntp events
no debug ntp events
To enable debug switch of NTP event
information.
63.3 Typical Examples of NTP Function
A client switch wanted to synchronize time with time server in network, there is two time server in network, the
one is used as host, the other is used as standby, the connection and configuration as follows (Switch A and
Switch B are the switch or route which support NTP server ):
The configuration of Switch C is as follows: (Switch A and Switch B may have the different command because
of different companies, we not explain there, our switches are not support NTP server at present)
Switch C:
Switch(config)#ntp enable
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ip address 192.168.1.12 255.255.255.0
Switch(config)#interface vlan 2
Switch(Config-if-Vlan1)#ip address 192.168.2.12 255.255.255.0
Switch(config)#ntp server 192.168.1.11
Switch(config)#ntp server 192.168.2.11
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63.4 NTP Function Troubleshooting
In configuration procedures, if there is error occurred, the system can give out the debug information.
The NTP function disables by default, the show command can be used to display current configuration. If the
configuration is right please use debug every relative debugging command and display specific information in
procedure, and the function is configured right or not, you can also use show command to display the NTP
running information, any questions please send the recorded message to the technical service center.
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Chapter 64 Summer Time Configuration
64.1 Introduction to Summer Time
Summer time is also called daylight saving time, it is a time system for saving energy sources. In summer the
time is advanced 1 hour to keep early hours, reduce the lighting, so as to save electrolighting. The rule that
adopt summer time is different in each country. At present, almost 110 countries implement summer time.
Compare with the standard time, usually set summer time 1 hour late, for example, when summer time is
implementing, 10:00 am of the standard time is considered 11:00 am of summer time.
64.2 Summer Time Configuration Task Sequence
1. Configure absolute or recurrent time range of summer time
Command Explanation
Global Mode
clock summer-time <word> absolute
<HH:MM> <YYYY.MM.DD> <HH:MM>
<YYYY.MM.DD> [<offset>]
no clock summer-time
Set absolute time range of summer time, start
and end summer time is configured with
specified year.
clock summer-time <word> recurring
<HH:MM> <MM.DD> <HH:MM> <MM.DD>
[<offset>]
no clock summer-time
Set recurrent time range of summer time,
every year the summer time begins from the
start time and end at the end time.
clock summer-time <word> recurring
<HH:MM> <week> <day> <month>
<HH:MM> <week> <day> <month>
[<offset>]
no clock summer-time
Set recurrent time range of summer time,
every year the summer time begins from the
start time and end at the end time.
64.3 Examples of Summer Time
Example1:
The configuration requirement in the following: The summer time from 23:00 on April 1st, 2012 to 00:00 on
October 1st, 2012, clock offset as 1 hour, and summer time is named as 2012.
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Configuration procedure is as follows:
Switch(config)# clock summer-time 2012 absolute 23:00 2012.4.1 00:00 2012.10.1
Example2:
The configuration requirement in the following: The summer time from 23:00 on the first Saturday of April to
00:00 on the last Sunday of October year after year, clock offset as 2 hours, and summer time is named as
time_travel.
Configuration procedure is as follows:
Switch(config)#clock summer-time time_travel recurring at 23:00 the first Sat. of Apr. and at 00:00 the
last Sun. of Oct.
64.4 Summer Time Troubleshooting
If there is any problem happens when using summer time, please check whether the problem is caused by
the following reasons:
Check whether command mode in global mode
Check whether system clock is correct
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Chapter 65 DNSv4/v6 Configuration
65.1 Introduction to DNS
DNS (Domain Name System) is a distributed database used by TCP/IP applications to translate domain
names into corresponding IPv4/IPv6 addresses. With DNS, you can use easy-to-remember and signification
domain names in some applications and let the DNS server translate them into correct IPv4/IPv6 addresses.
There are two types of DNS services, static and dynamic, which supplement each other in application. Each
time the DNS server receives a name query it checks its static DNS database first before looking up the
dynamic DNS database. Some frequently used addresses can be put in the static DNS database, the
reduction the searching time in the dynamic DNS database would increase efficiency. The static domain name
resolution means setting up mappings between domain names and IPv4/IPv6 addresses. IPv4/IPv6
addresses of the corresponding domain names can be found in the static DNS database when you use some
applications. Dynamic domain name resolution is implemented by querying the DNS server. A user program
sends a name query to the resolver in the DNS client when users want to use some applications with domain
name, the DNS resolver looks up the local domain name cache for a match. If a match is found, it sends the
corresponding IPv4/IPv6 address back to the switch. If no match is found, it sends a query to a higher DNS
server. This process continues until a result, whether success or failure, is returned.
The Domain Name System (DNS) is a hierarchical naming system for computers, services, or any resource
participating in the Internet. It associates various information with domain names assigned to such
participants. Most importantly, it translates humanly meaningful domain names to the numerical (binary)
identifiers associated with networking equipment for the purpose of locating and addressing these devices
world-wide. An often used analogy to explain the Domain Name System is that it serves as the "phone book"
for the Internet by translating human-friendly computer hostnames into IP addresses.
The Domain Name System makes it possible to assign domain names to groups of Internet users in a
meaningful way, independent of each user's physical location. Because of this, World-Wide Web (WWW)
hyperlinks and Internet contact information can remain consistent and constant even if the current Internet
routing arrangements change or the participant uses a mobile device. Internet domain names are easier to
remember than IP addresses such as 208.77.188.166(IPv4) or 2001:db8:1f70::999:de8:7648:6e8 (IPv6).
People take advantage of this when they recite meaningful URLs and e-mail addresses without having to
know how the machine will actually locate them.
The Domain Name System distributes the responsibility for assigning domain names and mapping them to
Internet Protocol (IP) networks by designating authoritative name servers for each domain to keep track of
their own changes, avoiding the need for a central register to be continually consulted and updated.
In general, the Domain Name System also stores other types of information, such as the list of mail servers
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that accept email for a given Internet domain. By providing a world-wide, distributed keyword-based
redirection service, the Domain Name System is an essential component of the functionality of the Internet.
65.2 DNSv4/v6 Configuration Task List
1. To enable/disable DNS function
2. To configure/delete DNS server
3. To configure/delete domain name suffix
4. To delete the domain entry of specified address in dynamic cache
5. To enable DNS dynamic domain name resolution
6. Enable/disable DNS SERVER function
7. Configure the max. number of client information in the switch queue
8. Configure the timeout value of caching the client information on the switch
9. Monitor and diagnosis of DNS function
1. To enable/disable DNS function
Command Explanation
Global Mode
ip domain-lookup
no ip domain-lookup
To enable/disable DNS dynamic lookup
function.
2. To configure/delete DNS server
Command Explanation
Global Mode
dns-server {<ip-address> |
<ipv6-address>} [priority <value>]
no dns-server {<ip-address> |
<ipv6-address>}
To configure DNS server, the no form of this
command deletes DNS server.
3. To configure/delete domain name suffix
Command Explanation
Global Mode
ip domain-list <WORD>
no ip domain-list <WORD> To configure/delete domain name suffix.
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4. To delete the domain entry of specified address in dynamic cache
Command Explanation
Admin Mode
clear dynamic-host {<ip-address> |
<ipv6-address> | all}
To delete the domain entry of specified
address in dynamic cache.
5. To enable DNS dynamic domain name resolution
Command Explanation
Global Mode
dns lookup {ipv4 | ipv6} <hostname> To enable DNS dynamic domain name
resolution.
6. Enable/disable DNS SERVER function
Command Explanation
Global Mode
ip dns server
no ip dns server Enable/disable DNS SERVER function.
7. Configure the max. number of client information in the switch queue
Command Explanation
Global Mode
ip dns server queue maximum
<1-5000>
no ip dns server queue maximum
Configure the max. number of client
information in the switch queue.
8. Configure the timeout value of caching the client information on the switch
Command Explanation
Global Mode
ip dns server queue timeout <1-100>
no ip dns server queue timeout
Configure the timeout value of caching the
client information on the switch.
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9. Monitor and diagnosis of DNS function
Command Explanation
Admin Mode
show dns name-server To show the configured DNS server
information.
show dns domain-list To show the configured DNS domain name
suffix information.
show dns hosts To show the dynamic domain name
information of resolved by switch.
show dns config Display the configured global DNS
information on the switch.
show dns client Display the DNS Client information
maintained by the switch.
debug dns {all | packet [send | recv] |
events | relay}
no debug dns {all | packet [send | recv]
| events | relay}
To enable/disable DEBUG of DNS function.
65.3 Typical Examples of DNS
DNS SERVER IP: 219.240.250.101 IPv6: 2001::1
ip domain-lookup dns-server 219.240.250.101 dns-server 2001::1
INTERNET
SWITCH
Figure 65-1: DNS CLIENT typical environment
As shown in fig, the switch connected to DNS server through network, if the switch want to visit Sina Website,
it needn’t to know the IPv4/IPv6 address of Sina Website, only need is to record the domain name of Sina
Website is www.sina.com.cn. The DNS server can resolute out the IPv4/IPv6 address of this domain name
and send to switch, then the switch can visit Sina Website correctly. The switch is configured as DNS client,
basic configurations are as below: first to enable DNS dynamic domain name resolution function on switch,
and configure DNS server address, then with some kinds of tools such as PING, the switch can get
corresponding IPv4/IPv6 address with dynamic domain name resolution function.
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DNS SERVER IP:219.240.250.101 IPv6:2001::1
client SWITCH
INTERNET
Figure 65-2: DNS SERVER typical environment
The figure above is an application of DNS SERVER. Under some circumstances, the client PC doesn’t know
the real DNS SERVER, and points to the switch instead. The switch plays the role of a DNS SERVER in two
steps: Enable the global DNS SERVER function, configure the IP address of the real DNS server. After the
DNS SERVER function is globally enabled, the switch will look up its local cache when receiving a DNS
request from a client PC. If there is a domain needed by the local client, it will directly answer the client’s
request; otherwise, the switch will relay the request to the real DNS server, pass the reply from the DNS
Server to the client and record the domain and its IP address for a faster lookup in the future.
Switch configuration for DNS CLIENT:
Switch(config)# ip domain-lookup
Switch(config)# dns-server 219.240.250.101
Switch(config)# dns-server 2001::1
Switch#ping host www.sina.com.cn
Switch#traceroute host www.sina.com.cn
Switch#telnet host www.sina.com.cn
Switch configuration for DNS SERVER:
Switch(config)# ip domain-lookup
Switch(config)# dns-server 219.240.250.101
Switch(config)# dns-server 2001::1
Switch(config)# ip dns server
65.4 DNS Troubleshooting
In configuring and using DNS, the DNS may fail due to reasons such as physical connection failure or wrong
configurations. The user should ensure the following:
First make sure good condition of the TACACS+ server physical connection;
Second all interface and link protocols are in the UP state (use “show interface” command);
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Then please make sure that the DNS dynamic lookup function is enabled (use the “ip domain-lookup”
command) before enabling the DNS CLIENT function. To use DNS SERVER function, please enable it
(use the “ip dns server” command);
Finally ensure configured DNS server address (use “dns-server” command), and the switch can ping
DNS server;
If the DNS problems remain unsolved, please use debug DNS all and other debugging command and
copy the DEBUG message within 3 minutes, send the recorded message to the technical service center
of our company.
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Chapter 66 Monitor and Debug
When the users configures the switch, they will need to verify whether the configurations are correct and the
switch is operating as expected, and in network failure, the users will also need to diagnostic the problem.
Switch provides various debug commands including ping, telnet, show and debug, etc. to help the users to
check system configuration, operating status and locate problem causes.
66.1 Ping
Ping command is mainly used for sending ICMP query packet from the switches to remote devices, also for
check the accessibility between the switch and the remote device. Refer to the Ping command chapter in the
Command Manual for explanations of various parameters and options of the Ping command.
66.2 Ping6
Ping6 command is mainly used by the switch to send ICMPv6 query packet to the remote equipment,
verifying the accessibility between the switch and the remote equipment. Options and explanations of the
parameters of the Ping6 command please refer to Ping6 command chapter in the command manual.
66.3 Traceroute
Traceroute command is for testing the gateways through which the data packets travel from the source device
to the destination device, so to check the network accessibility and locate the network failure.
Execution procedure of the Traceroute command consists of: first a data packet with TTL at 1 is sent to the
destination address, if the first hop returns an ICMP error message to inform this packet can not be sent (due
to TTL timeout), a data packet with TTL at 2 will be sent. Also the send hop may be a TTL timeout return, but
the procedure will carries on till the data packet is sent to its destination. These procedures is for recording
every source address which returned ICMP TTL timeout message, so to describe a path the IP data packets
traveled to reach the destination.
Traceroute Options and explanations of the parameters of the Traceroute command please refer to traceroute
command chapter in the command manual.
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66.4 Traceroute6
The Traceroute6 function is used on testing the gateways passed through by the data packets from the source
equipment to the destination equipment, to verify the accessibility and locate the network failure. The principle
of the Traceroute6 under IPv6 is the same as that under IPv4, which adopts the hop limit field of the ICMPv6
and IPv6 header. First, Traceroute6 sends an IPv6 datagram (including source address, destination address
and packet sent time) whose HOPLIMIT is set to 1. When first route on the path receives this datagram, it
minus the HOPLIMIT by 1 and the HOPLIMIT is now 0. So the router will discard this datagram and returns
with a 「ICMPv6 time exceeded」 message (including the source address of the IPv6 packet, all content in the
IPv6 packet and the IPv6 address of the router). Upon receiving this message, the Traceroute6 sends another
datagram of which the HOPLIMIT is increased to 2 so to discover the second router. Plus 1 to the HOPLIMIT
every time to discover another router, the Traceroute6 repeat this action till certain datagram reaches the
destination.
Traceroute6 Options and explanations of the parameters of the Traceroute6 command please refer to
traceroute6 command chapter in the command manual.
66.5 Show
show command is used to display information about the system, port and protocol operation. This part
introduces the show command that displays system information, other show commands will be discussed in
other chapters.
Command Explanation
Admin Mode
show debugging Display the debugging state.
show flash Display the files and the sizes saved in the
flash.
show history Display the recent user input history
command.
show history all-users [detail]
Show the recent command history of all
users. Use clear history all-users
command to clear the command history of all
users saved by the system, the max. history
number can be set by history all-users
max-length command.
show memory Display content in specified memory area.
show running-config Display the switch parameter configuration
validating at current operation state.
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show running-config current-mode Show the configuration under the current
mode.
show startup-config
Display the switch parameter configuration
written in the Flash Memory at current
operation state, which is normally the
configuration file applied in next time the
switch starts up.
show switchport interface [ethernet
<IFNAME>]
Display the VLAN port mode and the
belonging VLAN number of the switch as
well as the Trunk port information.
show tcp
show tcp ipv6
Display the TCP connection status
established currently on the switch.
show udp
show udp ipv6
Display the UDP connection status
established currently on the switch.
show telnet login
Display the information of the Telnet client
which currently establishes a Telnet
connection with the switch.
show tech-support
Display the operation information and the
state of each task running on the switch. It is
used by the technicians to diagnose whether
the switch operates properly.
show version Display the version of the switch.
show temperature This command is not supported by switch.
show fan This command is not supported by switch.
66.6 Debug
All the protocols switch supports have their corresponding debug commands. The users can use the
information from debug commands for troubleshooting. Debug commands for their corresponding protocols
will be introduced in the later chapters.
66.7 System log
66.7.1 System Log Introduction
The system log takes all information output under it control, while making detailed catalogue, so to select the
information effectively. Combining with Debug programs, it will provide a powerful support to the network
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administrator and developer in monitoring the network operation state and locating the network failures.
The switch system log has following characteristics
Log output from four directions (or log channels) of the Console, Telnet terminal and monitor, log buffer
zone, and log host.
The log information is classified to four level of severities by which the information will be filtered
According to the severity level the log information can be auto outputted to corresponding log channel.
66.7.1.1 Log Output Channel
So far the system log can be outputted the log information through four channels:
Through Console port to the local console
Output the log information to remote Telnet terminal or monitor, this function is good for remote
maintenance
Assign a proper log buffer zone inside the switch, for record the log information permanently or
temporarily
Configure the log host, the log system will directly send the log information to the log host, and save it in
files to be viewed at any time
Among above log channels, users rarely use the console monitor, but will commonly choose the Telnet
terminal to monitor the system operation status. However information outputted from these channels are of
low traffic capacity and can not be recorded for later view. The other two channels---the log buffer zone and
log host channel are two important channels
SDRAM (Synchronous Dynamic Random Access Memory) and NVRAM (Non Vulnerable Random Access
Memory) is provided inside the switch as two part of the log buffer zone, The two buffer zone record the log
information in a circuit working pattern, namely when log information need to be recorded exceeds the buffer
size, the oldest log information will be erased and replaced by the new log information, information saved in
NVRAM will stay permanently while those in SDRAM will lost when the system restarts or encounter an power
failure. Information in the log buffer zone is critical for monitoring the system operation and detecting
abnormal states.
Note: the NVRAM log buffer may not exist on some switches, which only have the SDRAM log buffer
zone.
It is recommended to use the system log server. By configuring the log host on the switch, the log can
be sent to the log server for future examination.
66.7.1.2 Format and Severity of the Log Information
The log information format is compatible with the BSD syslog protocol, so we can record and analyze the log
by the systlog (system log protect session) on the UNIX/LINUX, as well as syslog similar applications on PC.
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The log information is classified into eight classes by severity or emergency procedure. One level per value
and the higher the emergency level the log information has, the smaller its value will be. For example, the
level of critical is 2, and warning is 4, debugging is leveled at 7, so the critical is higher than warnings which no
doubt is high than debugging. The rule applied in filtering the log information by severity level is that: only the
log information with level equal to or higher than the threshold will be outputted. So when the severity
threshold is set to debugging, all information will be outputted and if set to critical, only critical, alerts and
emergencies will be outputted.
The following table summarizes the log information severity level and brief description. Note: these severity
levels are in accordance with the standard UNIX/LINUX syslog.
Table 66-1 Severity of the log information
Severity Value Description
emergencies 0 System is unusable
alerts 1 Action must be taken immediately
critical 2 Critical conditions
errors 3 Error conditions
warnings 4 Warning conditions
notifications 5 Normal but significant condition
informational 6 Informational messages
debugging 7 Debug-level messages
Right now the switch can generate information of the following four levels
Restart the switch, mission abnormal are classified critical
Up/down interface, topology change, aggregate port state change of the interface are notifications
warnings
Outputted information from the CLI command is classified informational
Information from the debugging of CLI command is classified debugging
Log information can be automatically sent to corresponding channels with regard to respective severity levels.
Amongst the debugging information can only be sent to the monitor. Those with the Informational level can
only be sent to current monitor terminal, such as the information from the Telnet terminal configuration
command can only be transmitted to the Telnet terminal. Warnings information can be sent to all terminal with
also saved in the SDRAM log buffer zone. And the critical information can be save both in SDRAM and the
NVRAM (if exists) besides sent to all terminals. To check the log save in SDRAM and the NVRAM, we can use
the show logging buffered command. To clear the log save in NVRAM and SDRAM log buffer zone, we can
use the clear logging command.
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66.7.2 System Log Configuration
System Log Configuration Task Sequence:
1. Display and clear log buffer zone
2. Configure the log host output channel
3. Enable/disable the log executed-commands
4. Display the log source
5. Display executed-commands state
1. Display and clear log buffer zone
Command Description
Admin Mode
show logging buffered [ level {critical |
warnings} | range <begin-index>
<end-index>]
Show detailed log information in the log
buffer channel.
clear logging sdram Clear log buffer zone information.
2. Configure the log host output channel
Command Description
Global Mode
logging {<ipv4-addr> | <ipv6-addr>}
[ facility <local-number> ] [level
<severity>]
no logging {<ipv4-addr> | <ipv6-addr>}
[ facility <local-number>]
Enable the output channel of the log host.
The “no” form of this command will disable
the output at the output channel of the log
host.
logging loghost sequence-number
no logging loghost sequence-number
Add the loghost sequence-number for the
log, the no command does not include the
loghost sequence-number.
3. Enable/disable the log executed-commands
Command Description
Global Mode
logging executed-commands {enable |
disable}
Enable or disable the logging
executed-commands
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4. Display the log source
Command Description
Admin Mode
show logging source mstp Show the log information source of MSTP
module.
5. Display executed-commands state
Command Description
Admin Mode
show logging executed-commands
state
Show the state of logging
executed-commands
66.7.3 System Log Configuration Example
Example 1: When managing VLAN the IPv4 address of the switch is 100.100.100.1, and the IPv4 address of
the remote log server is 100.100.100.5. It is required to send the log information with a severity equal to or
higher than warnings to this log server and save in the log record equipment local1.
Configuration procedure:
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)# ip address 100.100.100.1 255.255.255.0
Switch(Config-if-Vlan1)#exit
Switch(config)#logging 100.100.100.5 facility local1 level warnings
Example 2: When managing VLAN the IPv6 address of the switch is 3ffe:506::1, and the IPv4 address of the
remote log server is 3ffe:506::4. It is required to send the log information with a severity equal to or higher
than critical to this log server and save the log in the record equipment local7.
Configuration procedure
Switch(config)#interface vlan 1
Switch(Config-if-Vlan1)#ipv6 address 3ffe:506::1/64
Switch(Config-if-Vlan1)#exit
Switch(config)#logging 3ffe:506::4 facility local7 level critical
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Chapter 67 Reload Switch after Specified Time
67.1 Introduction to Reload Switch after Specified Time
Reload switch after specified time is to reboot the switch without shutdown its power after a specified period of
time, usually when updating the switch version. The switch can be rebooted after a period of time instead of
immediately after its version being updated successfully.
67.2 Reload Switch after Specified Time Task List
1. Reload switch after specified time
Command Explanation
Admin Mode
reload after {[<HH:MM:SS>] [days
<days>]}
Reload the switch after a specified time
period.
reload cancel Cancel the specified time period to reload
the switch.
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Chapter 68 Debugging and Diagnosis for Packets Received and Sent by CPU
68.1 Introduction to Debugging and Diagnosis for Packets
Received and Sent by CPU
The following commands are used to debug and diagnose the packets received and sent by CPU, and are
supposed to be used with the help of the technical support.
68.2 Debugging and Diagnosis for Packets Received and Sent
by CPU Task List
Command Explanation
Global Mode
cpu-rx-ratelimit protocol
<protocol-type> <packets>
no cpu-rx-ratelimit protocol
[ <protocol- type> ]
Set the max. rate of the CPU receiving packets of the
protocol type, the no command set the max. rate to default.
clear cpu-rx-stat protocol
[ <protocol-type> ]
Clear the statistics of the CPU received packets of the
protocol type.
Admin Mode
show cpu-rx protocol
[ <protocol-type> ]
Show the information of the CPU received packets of the
protocol type.
debug driver {receive|send}
[interface {<interface-name>
|all}] [protocol {<protocol-type>
|discard |all}][detail]
Turn on the showing of the CPU receiving or sending packet
informations.
no debug driver {receive |send} Turn off the showing of the CPU receiving or sending packet
informations.
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Chapter 69 Dying Gasp Configuration
69.1 Introduction to Dying Gasp
Dying gasp is power failure alarm function. It means that at the case of power failure, the switch can also send
information through the ethernet ports to notice the other switch that it is power failure.
Dying gasp is enabled as default, but it could run normally with the snmp management function. So the layer 3
interface should be configured on switch and make it connect to snmp management server. snmp trap should
be configured orderly.
69.2 Dying Gasp Typical Examples
The dying gasp function of the switch is enabled as default, but it could run normally with the snmp
management function.
Below are the configuration steps:
Switch(config)#snmp-server enable
Switch(config)#snmp-server securityip X.X.X.X
Switch(config)#snmp-server host X.X.X.X v2c switch
Switch(config)#snmp-server enable traps
Switch(config)#interface vlan N
Switch(config-if-vlanN)ip address Y.Y.Y.Y 255.255.255.0
69.3 Dying Gasp Troubleshooting
If there is something wrong when configuring dying gasp function, please check out if it is because of the
following reasons:
Make sure the layer 3 interface has been configured and connected to snmp server.
Make sure the address of snmp server. More than one snmp server address can be configured on
switch, but dying gasp trap packets will be sent to the last configured server when it is power failure.
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Chapter 70 PoE Configuration
70.1 Introduction to PoE
PoE (Power over Ethernet) is a technology to provide direct currents for some IP-based terminals (such as IP
phones, APs of wireless LANs and network cameras) while transmitting data to them. Such DC-receiving
devices are called PD (Powered Device). The max. distance of reliable power supply provided by PoE is 100
meters.
IEEE 802.3af standard is a new PoE standard, and an extension to the current Ethernet standard by adding
new items on power supply via network cables to IEEE 802.3 standard. It is also the first international
standard on power distribution.
The application of PoE used to be in two areas: IP phone and 802.11 wireless network, however, along with
the development of this technology, many applications with more practical meanings have emerged and
benefited from PoE, such as video monitoring, integrated building management solution, and remote video
service booth. All these existing and predictably more of such applications arouse needs for switches
supporting PoE.
70.2 PoE Configuration
The PoE Configuration Task List:
1. Globally enable or disable PoE
2. Globally Set the Max. Output Power
3. Globally set power management mode
4. Globally set non-standard PD detection mode
5. Globally enable or disable the allowed high-inrush current when nonstandard PD is powered
instantaneously
6. Enable or disable PoE on specified ports
7. Set the max. output power on specified ports
8. Set the power priority on specified ports
1. Globally Enable or Disable PoE
Command Explanation
Global Mode
power inline enable
no power inline enable Enable/disable PoE globally.
2. Globally set the max.. output power
Command Explanation
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Global Mode
power inline max
<max-wattage>
no power inline max
Globally set the max. output power of PoE.
3. Globally set the power management mode
Command Explanation
Global Mode
power inline police enable
no power inline police enable Enable/disable the power priority management policy mode.
4. Globally set non-standard PD detection mode
Command Explanation
Global Mode
power inline legacy enable
no power inline legacy enable
Set whether or not to provide power for non-standard IEEE
PD.
5. Globally enable or disable the allowed high-inrush current when nonstandard PD is powered
instantaneously
Command Explanation
Global Mode
power inline high-inrush enable
no power inline high-inrush
enable
Enable/disable the allowed high-inrush current when
nonstandard PD is powered instantaneously.
6. Enable or disable PoE on specified ports
Command Explanation
Port Mode
power inline enable
no power inline enable Enable/ disable PoE.
7. Set the max. output power on specified ports
Command Explanation
Port Mode
power inline max
<max-wattage>
no power inline max
Set the max. output power on specified ports.
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8. Set the power priority on specified ports
Command Explanation
Port Mode
power inline priority {critical |
high | low} Set the power priority on specified ports.
70.3 Typical Application of PoE
Requirements of Network Deployment
Set the max. output power of SGS-6340-24P4S to 370W, assuming that the default max. power can satisfy
the requirements.
Ethernet interface 1/0/2 is connected to an IP phone.
Ethernet interface 1/0/4 is connected to a wireless AP.
Ethernet interface 1/0/6 is connected to a Bluetooth AP.
Ethernet interface 1/0/8 is connected to a network camera.
The IP phone connected to Ethernet interface has the highest-level power supply priority: critical, which
requires the power supply to the newly connected PD being cut off if it causes PSE power-overload (i.e.
adopting the priority policy of PD power management).
Power of subordinate AP devices connected to Ethernet interface 1/0/6 should not exceeds 9000mW.
Topology of Network
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Configuration Steps:
Globally enable PoE:
Switch(Config)# power inline enable
Globally set the max. power to 370W:
Switch(Config)# power inline max. 370
Globally enable the priority policy of power management:
Switch(Config)# power inline police enable
Set the priority of Port 1/0/2 to critical:
Switch(Config-Ethernet1/0/2)# power inline priority critical
Set the max. output power of Port 1/0/6 to 9000mW:
Switch(Config-Ethernet1/0/6)#power inline max. 9000
70.4 PoE Troubleshooting Help
If problems occur on using PoE, please check: When the global value of Power Remaining is less than 15W, due to the power source protection mechanism, the power supply to new PDs will be cut off in first-come-first-serve mode, while the existing low-priority devices will also be disconnected in priority policy mode. If the Power Remaining is over 15W, say 16W, any
newly connected device with a power no more than 15W can get its power supply normally, without affecting other devices. Such a power supply buffer of 15W is designed for power source protection, and calls for special attention.
The displayed value of power might over the value of max. This involves the relationship between the displayed power and the actual power, for instance:
The power set on the port: A, represents the actual output PoE power The displayed power: B, represents the total power of the port (total current × total voltage)
The power loss set on the port: C, represents power loss of the internal Sensor ohmic resistance, MosFet etc.
Then: B=A+C If the power is set as A=500mW, according to the following table, the compensating current will be I=2.44mA (500mW/50V＝10mA assuming the current working voltage is 50V), plus the compensating power C=50V×
2.44mA＝122mA
B=A+C=500+122=622mW. So, only when the displayed power reaches 622mW, the PD will be disconnected Table:
Max. Working Current (mA) Compensating Current (mA)
50 2.44
100 4.88
150 9.76
200 17.08
250 24.41
350 31.73
